Acquisitions: Motivations & Challenges Essay

a. Identify five main motivations (discussed in class) for acquiring a company. Provide a specific, real-world acquisition example for each motivation. b. Which three motivations are most relevant to Paragon Tool’s potential acquisition of MonitoRobotics in the Growing for Broke case? c. Identify the four main challenges (discussed in class) when executing a corporate acquisition. Provide a specific, real-world acquisition example for each challenge. 2. Blue Ocean Strategy a. Draw a strategy canvas for the Nintendo Wii and briefly describe what it says about why Nintendo has been successful in such a competitive industry. Include the Sony Playstation and the Microsoft Xbox on the canvas. b. Identify and briefly describe the six paths to finding Blue Oceans. Give a specific, real-world example of each path (other than the examples I gave in class). 3. Cisco Systems’ Acquisition Strategy a. Outcomes of nearly 75% of corporate acquisitions fail to meet managerial expectations. Identify 7 reasons why Cisco Systems has been more successful than most other companies in executing over 100 acquisitions (see the two attached articles). b. Identify 3 reasons why Cisco Systems began having trouble with its acquisition strategy. 4. Diversification at Starbucks a. Illustrate and concisely explain the Boston Consulting Group’s Growth-Share Matrix. Make sure you identify: i. the dimensions upon which the Matrix is based ii. each type of businesses embodied in the Matrix’s quadrants iii. the three functional assumptions of the model b. Specifically apply the model to Starbuck’s product diversification efforts since the 1990s (see the attached article). c. Concisely explain two reasons why BCG’s Growth-Share Matrix might not accurately reflect Starbucks’ historical development. 5. Google’s International Strategy a. Identify and briefly explain the three types of international strategy. b. Identify Google’s international strategy and explain why Google Finance would have only been possible under that strategy (see Tom Friedman’s â€Å"Outsourcing, Schmoutsourcing! Out Is Over† article below). c. Give a specific, real-world example of each of the other two types of international strategy. 6. Reconfiguration in the Personal  Computer (PC) Industry a. Identify and briefly explain six distinct methods that firms can use to acquire the resources and capabilities they need to develop new products and businesses. b. Drawing on our discussion of the strategic sourcing framework, briefly describe and/or illustrate the relative advantages and disadvantages of these methods. c. Both PC software and hardware manufacturers have been forced to adapt to the rapidly evolving industry in order to survive. Using the PC industry, provide a specific example of 5 of these 6 methods. d. Briefly explain why Xerox may be greatest success and the worst failure in the history of the PC industry. 7. Outsourcing at GM a. Concisely describe the Strategic Sourcing Framework. Be sure to identify the relevant costs/advantages associated with the make-or-buy decision. b. In February 2006, GM announced a â€Å"huge package of outsourcing contracts.† See the attached article. Using the Strategic Sourcing Framework and our class discussions of GM, explain why GM chose to do this. c. Concisely describe the disadvantages GM faced in choosing to outsource, like this. 8. In the early 2000s, Boeing began aggressively outsourcing the development and production of the 787 airplane design. By late 2008, Boeing managers admitted that they made some mistakes in pursuing the outsourcing strategy and that Boeing would significantly curtail outsourcing. List Boeing’s initial motivations for outsourcing and the reasons behind its subsequent change of heart. 9. Diversification a. Concisely describe and explain the relationship between diversification and corporate performance. b. Give one example each of companies with very low diversification, very high diversification, and moderate diversification. Make sure these examples accurately reflect the relationship you described in part a. c. In class, I argued that Tyco could be considered an exception to the generally understood relationship between diversification and performance. Explain why you think this is true or untrue. d. Regardless of how you answered part c, identify 4 or 5 ways that Tyco’s diversification strategy is different from typical corporations’ corporate strategy. 10. Hybrid Engine Technology & Industry Evolution a. Concisely explain what type of industry disruption best describes Toyota’s  introduction of the first hybrid engine car targeted for the United States mass market. c. Give a specific historical example (from any industry) of the other major type industry disruption. d. Using a technological S-curve graph (Walker Figure 4.5), illustrate the evolution of the automobile engine. In your illustration, make sure you capture the development of 1) hybrid, 2) hydrogen fuel cell, and 3) standard gas-powered combustion engine technologies. Also include in the illustration indicators of today’s date in addition to the dates at which each technology was (will be) introduced to the U.S. mass market. e. Concisely explain Utterback’s model of innovation (Walker Figure 4.4). f. Use Utterback’s model to specifically and concisely explain why hydrogen fuel cell engines might not be commercially viable for a very, very lo ng time. How Cisco Makes Takeovers Work With Rules, Focus On Client Needs By Mike Angell, Investor’s Business Daily Investor’s Business Daily Investing in technology is risky. Just ask Cisco Systems. In 1997, the networking leader bought Dagaz, a company that made gear for digital subscriber lines. Dagaz wasn’t solid, and Cisco had to buy another company to get the right product. â€Å"You have to be ready to take those risks,† said Ammar Hanafi, Cisco’s business development manager. He’s been involved in almost every Cisco takeover since 1998. But Dagaz was an exception among the 70 companies Cisco has bought in the last seven years. That makes Cisco an exception, too. According to a study by consultant A.T. Kearney, more than half of mergers don’t work out. Here are some of Cisco’s rules: Stay close to home – 73% of Cisco’s targets make network gear. Deals make geographic sense, too. They’re close to a Cisco unit or a key talent capital. Get early wins – targets have products customers want right now. Familiarity – Cisco has stakes in 15% of its targets. Think small – Cisco buys start-ups mostly Management stays – and quickly learns the Cisco way. Beyond those factors, Cisco looks at what the target firm wants to accomplish, the needs of Cisco’s customers and how targets fit. â€Å"Cisco is the best example of a company with a well-established acquisition and post merger strategy,† Kearney’s Max Schroeck said. Many failed mergers stem from companies trying to enter new markets or just cut  costs. Successful mergers are between companies in related lines, the stud y says. That means joining people who share knowledge and experience. Cisco stays close to network gear. It strays, but not far. Smaller forays have been in Net-based phone gear (3%), software for content delivery (15%) and wireless gear (8%). Customer Focus â€Å"We’re always focused on our customers’ wants and needs,† Hanafi said. â€Å"We’re always expanding the range of products we have as our customers’ own networks expand.† The best example may be Cisco’s first acquisition in 1993. CEO John Chambers, then Cisco’s top salesman, was negotiating an order. But the client leaned toward a rival. So Cisco bought the rival, Crescendo Communications, for $ 89 million. Crescendo’s product was no â€Å"killer,† Hanafi said. But by the third generation, it brought in almost half of Cisco’s sales. â€Å"The first generation should be good enough for a customer,† Hanafi said. â€Å"The second generation is usually a great product. By the third, it should be a market leader.â⠂¬  Buy Vs. Invest But how does Cisco know this will be the case? Homework. Thirty people screen companies, probe market potential and talk to likely targets. Its engineers study products, and it queries customers. In some cases, this leads to an investment – one that helps Cisco learn about new technologies. If it’s a new market and product line, Cisco will invest. If the technology isn’t ready but looks right, Cisco will invest as well. â€Å"We’re always looking to enter new parts of the network,† Hanafi said. â€Å"Sometimes there are companies that are not as strategic, but we’d like to know what they do.† Of the 20 companies Cisco bought this year, it had stakes in eight. Overall, it has stakes in about 15% of its possible targets. Sometimes investments prompt Cisco to go with a rival. Two years ago, Cisco bought a stake in a company called Tellium that made an optical switch. Following some changes at Tellium, and after learning about that market, Cisco bought Monterey Networks instead for $ 500 million. Cisco still has a â€Å"passive† investment in Tellium but may sell its stake when it can, Hanafi says. For the most part, Cisco targets start-ups. Chambers doesn’t believe mergers of equals can work. The Kearney study agrees. It  said nearly one-third of mergers of equals destroy shareholder value. Cisco’s 1996 buy of StrataCom makes the point. At $ 4 billion, StrataCom was Cisco’s largest takeover to date. StrataCom’s sales force tou ted one data standard, Cisco’s another. Users were confused. â€Å"Integrating the two sales forces was more difficult,† Hanafi said. Geography’s Role Cisco also has a rule that targets must be physically near one another. This year, Cisco added a fourth company to its Israeli portfolio. And it added its second Canadian company, a software firm called PixStream. These areas are promising new high-tech hubs, and Cisco needs to â€Å"go where the talent is.† â€Å"People asked us why buy PixStream? It’s in Waterloo, Canada,† Hanafi said. â€Å"It’s right next to the University of Waterloo, a good school for engineers.† Though it may take up to two years to identify a potential acquisition, Cisco doesn’t waste time closing the deal. Hanafi has seen some sealed in as few as 10 days. Ultimately, Cisco buys talent. It woos people by telling them Cisco will help make their product No. 1. Integration Teams â€Å"We’re saying to them, ‘Use our sales force, our manufacturing size,’ † Hanafi said. â€Å"Come in and we’ll help make you a leader.† That’s kept 75% of acquired companies’ CEOs at Cisco. Cisco sets up a chain of command, and the CEO of the acquired company stays in charge. Integration is easier. Cisco has made integrating companies a discipline. Hanafi has a team of 10 people who run this process. They send up to 65 others from sales, human resources, manufacturing and finance to meet with every worker to discuss salaries, benefits and roles. †The first question people ask after being acquired by Cisco is, ‘What’s going to happen to my dentist?’ † Hanafi said. Cisco Shopped till It Nearly Dropped By John A. Byrne and Ben Elgin in San Jose, Calif., BusinessWeek It was an all-too-typical deal for Cisco Systems Inc. Monterey Networks Inc., an opticalrouting startup in which Cisco held a minority stake, was a quarry with no revenue, no products, and no customers  Ã¢â‚¬â€ just millions in losses it had racked up since its founding in 1997. Despite those deficits, Cisco plunked down a half-billion dollars in stock to buy the rest of the company in 1999. But within days of closing the deal, all three of Monterey’s founders, including its engineering guru and chief systems architect, walked out the door, taking with them millions of dollars in gains from the sale. †I came to the realization I wasn’t going to have any meaningful impact on the product by staying,† says H. Michael Zadikian, a Monterey founder. Eighteen months later, Cisco shut down the business altogether, sacking the rest of the management team and taking a $ 108 million write-off. That dismal tale hardly jibes with Cisco’s widespread reputation as an acquisitions whiz. Not since the conglomerate era has a company relied so heavily on its ability to identify, acquire, and integrate other companies for growth. CEO John T. Chambers believed that if Cisco lacked the internal resources to develop new products in six months, it had to buy its way into the market or miss the window of opportunity. Some put a new name on it: acquisitions and development, a way for the company to shortcut the usual research cycle. Its belief in the strategy has led Cisco to gobble up more than 70 companies in the past eight years. Analysts and academics heaped praise on Cisco’s acquisitions prowess in articles, books, and business-school case studies. In the early days, some of this praise was deserved, as Cisco morphed from a router company to a networking powerhouse. Its first acquisition, Crescendo Communications Inc., guided Cisco into the switching business, which generated $ 10 billion in sales last year. All told, acquisitions have laid the foundation for about 50% of Cisco’s business. But in early 1999, with exuberant investors enticing a growing number of unproven companies to go public, Cisco suddenly had to acquire companies at a much earlier stage. Cisco had long claimed an unprecedented success rate of 80% with its acquisitions. Chambers now says it fell to something like 50% during the Internet craze — still above the industry average. †We bet on products 12 to 18 months out,† concedes Chambers. †We took dramatically higher risks.† Chambers often maintained that his acquisition strategy was aimed at acquiring brainpower more than products. But an analysis of the 18 acquisitions Cisco made in 1999 shows that Monterey was no fluke. Many of the most valuable employees, the highly driven founders and chief executives of these acquired companies, have since  bolted, taking with them a good deal of the expertise and experience for which Cisco paid top dollar. The two founders of StratumOne Communications Inc., a maker of optical  semiconductors purchased for $ 435 million, left Cisco. The chief exec of GeoTel Communications Corp., a call-routing outfit acquired for $ 2 billion, walked out after nine months. So did the CEOs or founders of Sentient Networks, MaxComm Technologies, WebLine Communications, Tasmania Network Systems, Aironet Wireless Communications, V-Bits, and Worldwide Data System s — all high-priced acquisitions in 1999. Some simply felt Cisco had become too big and too slow. †People who crave risk don’t do so well at Cisco,† says Narad Networks CEO Dev Gupta, who sold Dagaz and MaxComm Technologies Inc. to Cisco in 1997 and 1999, respectively. †Cisco focuses much more on immediate customer needs, less on high-wire technology development that customers may want two to three years out.† Chambers maintains that Cisco’s turnover rates are the best in high technology. †In our industry, 40% to 80% of the top management team and top engineers are gone within two years,† he says. †Our voluntary attrition rate is about 12% over two years.† Difficulty holding on to top talent was not the only flaw in the Cisco acquisition machine. Cisco often paid outrageous sums for these unprofitable startups — a total of $ 15 billion in 1999 alone. Even some of the deals that Cisco considers successful look pretty dreadful using simple math. Its 1999 acquisition of Cerent Corp., a maker of opticalnetworking gear, is a good example. Cisco paid $ 6.9 billion for the company, or $ 24 million for each of Cerent’s 285 employees, even though the company had never earned a penny of profit and had an accumulated deficit of $ 60 million. Even if earnings bounce back to 2000 levels of roughly $ 335 million, it would take Cisco about 20 years to recoup the purchase price. Of course, deals such as Cerent found their rationale in Wall Street math. If investors were willing to pay 100 times earnings for Cisco’s stock in 1999, then a Cerent profit of, say, $ 300 million could effectively increase the market cap of Cisco by some $ 30 billion. Call it bubble economics. Besides, many of these deals were done for highly inflated Cisco stock instead of  cash. Even so, that wampum could have been used to buy other assets that could have delivered greater returns. Only in the months since the bubble burst has it become evident just how muddled Cisco’s mergers-and-acquisitions strategy became. In its haste to do deals, Cisco often purchased companies it didn’t need or couldn’t use. In some cases, the buying spree led to overlapping, duplicative technologies, political infighting, and just plain wasted resources, as Monterey shows. †M&A works to some extent, but at Cisco, it got out of hand,† says Iqbal Husain, a former engineering executive at Cisco. After losing many of the leaders of these businesses, product delays and other mishaps were not uncommon. When Cisco closed down Monterey, for example, the company still hadn’t put a product out for testing, which alone would take as long as a full year. †By the time the product was there to test, the market wasn’t,† says Joseph Bass, former CEO of Monterey. Chambers says he has moved to correct the flaws. Its acquisition binge has slowed —  from 41 companies from 1999 through 2000 to just two purchases in 2001. While Chambers expects to do 8 to 12 acquisitions this year, he insists that market conditions will let Cisco wait at least until a target company has a proven product, customers, and management team before cutting a deal. †We’re making the decisions to acquire a company based on a later point in time, which dramatically lowers the risk,† Chambers says. Anything more ambitious, Cisco now knows, may be foolhardy. A Costly Acquisition Strategy Often lauded for its buyout successes, Cisco has purchased more than 70 companies in the past eight years. In 1999 alone, it paid $15 billion for 18 startups, many of which never delivered on their early promise. Here are the most noteworthy: COMPANY PRICE STATUS SKINNY CERENT $6.9 Alive and Although Cerent has generated $1 billion well billion in estimated sales for Cisco, two decades could be needed to recoup the steep price. PIRELLI $2.2 Alive but A disappointing attempt to bolster OPTICAL billion struggling Cisco’s long-haul optical networking. SYSTEMS But Pirelli’s technology still trails that of rivals. MONTEREY $500 Dumped This  upstart optical company never NETWORKS million in April produced a viable product, and Cisco cut its losses with a $108 million write-off in April. AMTEVA $170 Sold at a Lackluster revenue forced Cisco to million loss in July sell this unified-messaging business. MAXCOMM $143 Part of their Founders and key technologists walked TECHNOLOGIES million DSL strategy out soon after the deal closed. Data: BusinessWeek The Toronto Star April 28, 2006 Friday SECTION: BUSINESS; Pg. F01 LENGTH: 631 words HEADLINE: Starbucks develops taste for independent films BYLINE: Sharda Prashad, Toronto Star BODY: First it was coffee, then CDs, now it’s movies. Today, the independent flick Akeelah and the Bee will make its debut in theatres, with a marketing boost from Starbucks. The java giant is advertising the Lionsgate Entertainment Corp. film about spelling bees, starring Laurence Fishburne and Angela Bassett, by using promotional coffee sleeves, coasters and displays in stores. Neither party has disclosed the amount of cash that’s changing hands in this deal, other than divulging Starbucks will be receiving a cut of the film’s profits for its marketing efforts. And when the DVD goes on sale, it will get a share of those profits – the DVD, by the way, will be available at Starbucks. Akeelah’s soundtrack will also be flogged at the coffee house. â€Å"Our customer is the demographic that Hollywood needs as it is facing a double-digit decline in the box office and slowing DVD sales,† Howard Schultz, Starbucks’ chairman, told Business Week earlier this year. â€Å"We have a unique cross-section of assets – a foundation of trust and confidence in Starbucks – that can promote a move that our customers know is relevant.† But is the purveyor of java risking its strong brand appeal by moving away from its coffee core with this latest venture? Starbucks, named for a character in the literary classic Moby Dick, currently has 11,000 outlets in 37 countries and is planning to open 1,800 this year. Its long-term plan is to have 30,000 outlets around the world. â€Å"Starbucks doesn’t sell coffee, it sells a retail environment that’s chic, urban and  authentic,† says Jay Handelman, marketing professor at Queenà ¢â‚¬â„¢s University School of Business. â€Å"If they were just selling coffee, why would they (customers) pay $4?† Since Starbucks is in the business of selling an urban experience, the professor says, the foray into a movie such as Akeelah and the Bee is consistent with that brand since the film is an urban, intellectual tale. If the movies and coffee were selling different experiences, the brand strategy wouldn’t work since customers would be confused about what Starbucks stood for, adds Andrea Wojnicki, marketing professor at University of Toronto’s Rotman School of Management. Should the movie do poor box office sales, it won’t necessarily affect the Starbucks brand, she says. Starbucks is about connoisseurship, she argues. It introduced people to the subtleties of coffee and it’s attempting to do the same with its CDs, which it started selling in 1995. The CD venture has also involved an urban experience. In 2004, for example, it coproduced Ray Charles’ Genius Loves Company and last year it held exclusive distribution for Alanis Morissette’s Jagged Little Pill Acoustic. Should the movie become a box office flop, Starbucks isn’t necessarily in trouble, says Wojnicki. It could hold up its connoisseur flag and say its campaign is about appreciating art and not about flogging blockbusters. It could also be argued that Starbucks took a growth opportunity that has stretched its brand too far, argues Mary Crossan, business policy professor at the University of Western Ontario. â€Å"When they start to move into movies, they’re not leveraging their resources or capabilities (in coffee).† Starbucks has stated that it is not interested in producing movies, just promoting them, but Crossan warns that companies need be careful about taking focus away from the core business. And Starbucks has made some poor business choices. It has failed in previous ventures, including an attempt to get into the Internet business in the 1990s and an in-house magazine called Joe that folded after three issues. But Akeelah star Angela Bassett thinks the movie business is a good move for Starbucks. â€Å"Everybody’s got something to sell,† she told Newsweek. â€Å"You just have to be sure of what you’re trying to sell.† Copyright New York Times Company May 19, 2006 I was on my way from downtown Budapest to the airport the other day when my driver, Jozsef Bako, mentioned that if I had any friends who were planning to come to Hungary, they should just contact him through his Web site: www.fclimo.hu. He explained that he could show people online all the different cars he has to offer and they could choose what they wanted. †How much business do you get online?† I asked him. †About 20 to 25 percent,† the Communist-eraengineer-turned-limo-proprietor said. The former secretary of state James Baker III used to say that you know you’re out of office †when your limousine is yellow and your driver speaks Farsi.† I would say, †You know that the global economy is spinning off all kinds of new business models when your Hungarian driver has his own Web site in English, Magyar and German — with background music.† Jozsef’s online Hungarian limo company is one of many new business models I’ve come across lately that are clearly expanding the global economy in ways that are not visible to the naked eye. I was recently interviewing Ramalinga Raju, chairman of India’s Satyam Computer Services. Satyam is one of India’s top firms doing outsourced work from America, and Mr. Raju told me how Satyam had just started outsourcing some of its American work to Indian villages. The outsourcee has become the outsourcer. Mr. Raju said: †We told ourselves: if business process outsourcing can be done from cities in India to support cities in the developed world, why can’t it be done by villages in India to support cities in India. Things like processing employee records can be done from anywhere, so there is no reason it can’t be done from a village.† Satyam began with two villages a year ago and plans to scale up to 150. There is enough bandwidth now, even reaching big Indian villages, to parcel out this work, and the villagers are very eager. †The attrition level is low, and the commitment levels high,† Mr. Raju said. †It is a way of breathing economic life into villages.† It gives educated villagers a chance to stay on the land, he said, and not have to migrate to the cities. A short time later I was interviewing Katie Jacobs Stanton, a senior product  manager at Google, and Krishna Bharat, founder of Google’s India lab. They told me that Google had just launched Google Finance, but what was interesting was that Google Finance was entirely conceived by the Google team in India and then Google engineers from around the world fed into that team — rather than the project’s being driven by Google headquarters in Silicon Valley. It’s called †around sourcing† instead of outsourcing, because there is no more †out† anymore. Out is over. †We don’t have the idea of two kinds of engineers — ones who think of things and others who implement them,† Ms. Stanton said. †We just told the team in India to think big, and what they came back with was Google Finance.† Mr. Bharat added: †We have entered the generation of the virtual office. Product development happens across the global campus now.† Last story. I’m in gray Newark speaking to local businessmen. I meet Andy Astor, chief executive of EnterpriseDB, which provides special features for the open-source database called PostgreSQL. His primary development team, he tells me, consists of 60 Pakistani engineers in Islamabad, who interact with the New Jersey headquarters via Internet-based videoconferencing. †The New Jersey team — software architects, product managers and executives — comes to work a couple of hours early, while the Islamabad team comes in late, and we have at least five to six hours per day of overlap,† Mr. Astor said. †We therefore have multiple face-to-face meetings every day, which makes a huge difference for communication quality. We treat videoconference meetings as if we were all in the same room.† What all these stories tell me is that we are seeing the emergence of collaborative business models that were simply unimaginable a decade ago. Today, there are so many more tools, so many more ideas, so many more people able to put these ideas and tools together to discover new things, and so much better communications to disseminate these new ideas across the globe. If more countries can get just a few basic things right — enough telecom and bandwidth so their people can get connected; steadily improving education; decent, corruption-free economic governance; and the rule of law — and we can find more sources of clean energy, there is every reason for  optimism that we could see even faster global growth in this century, with many more people lifted out of poverty. GM’s Landmark in IT Outsourcing By Steve Hamm – BusinessWeek – 2/2/2006 A huge package of outsourcing contracts announced Feb. 2 by General Motors seems to signal shifting fortunes in the $600 billion-a-year information-technology services industry. EDS, GM’s longtime primary supplier, lost ground, while Hewlett-Packard’s sometimes-overlooked services unit got a big lift. The profile of India’s tech industry rose when GM named one of the country’s leading companies, Wipro, as a tier-one supplier. All told, about $7.5 billion in five-year contracts were awarded. Another $7.5 billion in contracts are expected to be parceled out as new projects come up over the next couple of years. EDS, which formerly had about two-thirds of GM’s outsourcing business, still has the biggest share. It got contracts worth $3.8 billion — or about half of the business. HP’s contracts totaled $700 million, and GM called it out as one of t he major gainers. IBM got $500 million in contracts. FINANCIAL SHADOW. The package is significant beyond its sheer size because it’s an indication of how GM Chief Information Officer Ralph Szygenda is reshaping the way the company handles tech outsourcing. He handed contracts in large chunks to companies that will handle them on a global basis rather than country by country. Also, GM and the tech suppliers worked together to create new standards for managing technology, which means all suppliers will do things in a uniform way. Szygenda says the new strategy will allow GM to improve global collaboration while assuring reliability of its computing systems and cutting costs. â€Å"It lets GM focus on innovation rather than spending a lot of time on managing its suppliers,† he said at a press conference. GM’s financial woes cast a shadow over the announcement, however. The carmaker reported a $4.8 billion quarterly loss on Jan. 26. While Szygenda said low prices were only a secondary impetus behind the way he structured the outsourcing contracts, some suppliers didn’t even participate in the bidding, most notably, Accenture. Others said they didn’t bid on all of the pieces because they were concerned they wouldn’t make enough money on them. â€Å"A BIG KICK.† Yet  those who did win contracts were jubilant. â€Å"HP selectively bid on areas where we know we can do a great job and where focus was on core areas of importance to HP and GM,† says Steve Smith, senior vice-president of HP Services. His business is often overshadowed by IBM and Accenture, but it has been gaining momentum lately. Its revenues grew 6% in HP’s fourth quarter, to $3.9 billion. Last quarter, IBM’s services revenues were in the doldrums, declining 5%, to $12 billion. Wipro had already been doing some work for GM, but the new package gives it a credibility lift. Its contracts were worth $300 million over five years. Wipro Executive Vice-President Girish Paranjpe says the company is delighted to be picked. â€Å"It’s a huge morale booster for us to be able to play with the big boys,† he says. â€Å"Also, because we’re the only tier-one player GM picked from India, it’s a big kick for us.† If GM’s new strategy for managing outsourcing works well, it could become a model for other large corporations. The package has five-year contracts instead of the more traditional 10-year pacts and splits the work up among several suppliers instead of relying predominantly on one. â€Å"This is a tipping point for IT,† says Robert McNeill, principal analyst at Forrester Research. â€Å"Organizations will have to add skills to their vendor management function and make transition management a key for success when moving to a more flexible services model.† Another lesson from the contract: Even financially troubled companies are spending big on IT. That’s great news for the tech titans that got a bigger piece of the GM pie. It should even provide solace to EDS, however diminished its share.

Facebook Should Be Banned

Social Network: an online community of people with a common interest who use a Web site or other technologies to communicate with each other and share information, resources(dictionary. com). There are almost 500 million users of social networks and spent over 700 billion minutes a month using them. Is this hindering our social skills? There are many ways that people interact with each other such as e-mail, texting, a social network but the least used interaction is face to face.A negative impact that social networks have on our relationships is that social networks might strengthen our relationship with acquaintances and people we don’t see often; social networks weaken our strong relationships and also bring about physical social isolation. The term â€Å"social network† leads you to believe that you are in fact being social when these sites are used more for a phone book or search engine.Instead of calling your friend and asking what they have planned for the night o r weekend, you can just look at their posts to find out. This contact is very impersonal and allows the least amount of interaction between two parties Social Networks allow you to overestimate the level of intimacy you have with someone. Social networks allow you to think that a person is more committed to a relationship or friendship more than they actually are. You need to be sure you are putting in a balanced time of online and offline relationships.According to a study by John Cacioppo (researcher at the University of Chicago), those who use social networks are more susceptible to the emotional contagion effects. An emotional contagion is the tendency to catch and feel emotions that are similar to and influenced by those of others. In his studies, it was found that loneliness alone was transmitted through social networks. Also, his study showed that 52% of those who have direct social network interactions with a lonely person they too will become lonely.Those who have a â€Å" friend of a friend† connection with said person will be 25% more lonely. You’ve probably also seen that sometimes normal courtesy and politeness—aspects we would utilize in our face-to-face interactions are sometimes missing in the online space, that we would use in face to face interactions. Many of these social networks have a chat feature. Because of this many people don’t pick up on humor, sarcasm, and sympathy. Along with this, if you were in a face to face interaction you have the added facial expressions and body language.Along with this chat feature people don’t have to talk directly so it is easy to hide behind the internet because you won’t have to directly address the problem. Because of social networking many people lose their ability to hold a conversation. Many people who use social networks lose the ability to spell correctly because they use shorthand such as U, tomoro, k and many others. Social Networks are very harmful, but if you balance out your online and offline relationships and don’t let social networks become your ‘hangout’, it shouldn’t be a problem.

The American Industial Revolution Period

The growth in large-scale industry and labor unions in the second half of the nineteenth century can be explained in many ways. Unlike earlier in the century, now there were broad markets, fast expansion in good economic times, thus causing a rise in demand for more goods. Additionally, new inventions with development in big business caused large scale industrialization to become possible. Lastly, companies† ability to employ mass numbers of people to work in their factories for cheap further encouraged industries† growth. With companies hiring people to do hard work for cheap, labor unions form. Generally, as industries grew and grew the working conditions for the workers got worse and worse, encouraging an increase and growth of labor unions. America was a growing country. The expansion west needed industrial recourses. The railroad itself encouraged the industries of steel, coal, wood, glass and rubber. The expansion west was not the only thing that encouraged the growth of industry, good economic times and a rise in population fueled the growth of industry. People would want more â€Å"stuff† and houses would need to be built as well as highrise buildings in urban centers to accommodate the density of people in the cities. All these factors caused a rise in demand for industrial goods in a large market. There is more reason, though, that large-scale industries were growing. New inventions helped a great deal in making the large-scale manufacturing of industrial goods possible. The Bessemer process, for example, helped the manufacturing of steel in the steel industry, made it possible to produce large quantities of steel in a relatively short period of time. The invention of electric power by Thomas Edison allowed factory machinery to be run by electricity, cutting the cost of employing people to run the machinery while increasing the productivity of the machines. Always increasing productivity, these inventions and others like it were essential to progression of big industry. these were harnessed and effectively put into use by big businesses. Big businesses were the economic powers behind the growth of their industries. With corporations, unlike earlier, businesses could outlive their founders so that they could be allowed to thrive without having to worry and the death of the founder because with shares in the stock market, people could own parts of the company, there was never one person who was the sole owner. Additionally, in the late nineteenth century, there weren†t regulations which allowed the businesses to grow in ways which it wouldn†t be allowed to grow today. Often times, vertical integration allowed several types of industries to be grouped under one big company thus securing their operation. All these things helped the businesses prosper. Since the big businesses were behind the large-scale industries, the industries prospered too. Essential to the growth of large scale industry are the workers. Between 1870 and 1890, 8 million immigrants came to America for a better life, they ended up working in factories. Unlike the native workers, the immigrants were willing to work for cheap. This let the industry cut the cost of employing workers, in fact, many industries went to European sources to find workers for more cheap labor. The native Americans who, generally, were driven from the countryside got the higher paying supervisory jobs in the industries. So this â€Å"pool† of labor further allowed the large scale industries to grow more. The working conditions in these industries were horrible. Cutting costs in an industry was a big deal. Unfortunately, most of the time, cutting costs meant long hours for the workers, lower wages and requirements on the amount of work you do in a day which was usually too much. Because of these bad conditions labor unions were formed to protest against them, but mostly to force the companies to higher wages, lower hours or better working conditions. Since workers were essential to the operation of the industries, the labor unions often organized strikes to demand change in wage, hours etc†¦ In 1877 when wages for the workers in the Baltimore and Ohio railroad were cut by 20% there was the first nationwide strike that set the path for an era of confrontation between labor unions and management. Often, federal troops and state militia intervened because the strikes got violent and the movement collapsed but sometimes strikes were successful. The industrial revolution between 1865 and 1900 set a period of economic growth. The success of this industrial growth was due to a combination of contributing factors. A rise in demand for industrial goods along with growth in big business were the essential things in causing the growth of large-scale industry. Additionally new inventions that helped the manufacturing of these goods and cheap labor encouraged further this growth. In the big picture, this industrialization of the country fueled the growth of it in area, in population and finally, in economy.

The Creation Of High Levels Of Job Satisfaction Essay

The Creation Of High Levels Of Job Satisfaction - Essay Example Moreover, according to Chen et al (2002), internalization of organizational values and systems lead to increased organizational commitment levels of employees, enhancing an individual’s intrinsic motivation to display higher levels of on-the-job performance. â€Å"Job satisfaction refers to an employee’s overall sense of well-being at work† (Biswas 2011: 96), and relates to intrinsic, extrinsic and social satisfaction. It enhances work performance, and has a positive correlation with organizational citizenship behavior. Thesis Statement: The purpose of this paper is to investigate and discuss the statement that if employees’ performance at soaring levels has to be achieved, it is necessary to create high levels of job satisfaction among the employees. There is a strong relationship between organizational support, job satisfaction and employee performance. Organizational citizenship and work performance are also related to leader supportiveness as well as f ollower job satisfaction. Perceived organizational support is the extent to which the organization values employees’ contributions and is concerned about their well-being. A supportive organization shows commitment towards its workers (Miao & Kim 2010). Theorists of organizational support state that a high level of perceived organizational support improves work attitudes and creates effective work behavior based on two reasons. First, these beneficial outcomes result from a process of social exchange. The work of researchers Eisenberger, Cummings, Armeli and Lynch (1997) suggests that workers examine the discretionary actions and infer the extent to which they are being supported. They then seek to compensate for this favorable treatment, thereby becoming more hard-working and committed to their work and the organization.

Personal Media Inventory Essay Example | Topics and Well Written Essays - 1250 words

Personal Media Inventory - Essay Example As the research declares television images are reproduced on screens which can either be colored or limited to black and white. Televisions have the ability to receive signals and reproduce them on screens. With technology, it is possible to have televisions which can stream media content without relying on the analogue signals used in the past. News and occurrences across the country and beyond are relayed through the television. One can also use a television to watch movies which are informative and entertaining. According to the report findings a newspaper is a printed publication which contains news, advertisements and other information that the producers considers important to reach the readers. Newspapers are better sources of information compared to television since one can keep the newspaper as a reference to a certain piece of information. They are both informative and entertaining. Magazines are closely related to newspapers. However, they are periodical publications which contains articles from various individuals on different topics. Whereas newspapers cover the contemporary issues in the society, magazines are more specific and dwell on a smaller niche of information. They cover a particular topic or area of interest. The internet is a global communication network that allows computers, phones, and other devices to communicate, connect and exchange information. It has taken over the entertainment and information industry considering that most people own cellular phones which can ac cess it.

Delivering Marketing Programs Essay Example | Topics and Well Written Essays - 1000 words

Delivering Marketing Programs - Essay Example In such a way, Red Bull began targeting and specifically marketing to key demographics by sponsoring different types of extreme sports and buying marketing space with regards to those activities that were primarily watched or engaged with by their demographic target. Such an inexpensive approach allowed the brand to position itself effectively with regards to rapidly gaining market share in integrating with this specific demographic around the globe. With respect to how this target market has changed over time, it has not. This represents both a positive and a negative for the Red Bull brand due to the fact that it present situation in which they are continuing to speak to the specific needs and tastes of their target audience; an activity that they have a great deal of experience in performing. However, this also represents a drawback due to the fact that there are a limited number of individuals within this particular demographic to which Red Bull can integrate and hope to sell the ir product (Barnett, 2013). As such, continuing to integrate with the same demographic as a means of targeting further sales is something of a lost cause. Conversely, the competition is positioned more along the traditional lines of marketing and brand imagery. The likes of Coca-Cola and Pepsi Co. have sought to exclusively promote and market key entries within the energy drink market by the traditional means of massive amounts of advertising and high costs of market entry (Red Bull, 2012). This necessarily places Red Bull at something of a strategic advantage due to the fact that the competition is continuing to integrate with very costly and prohibitively limited means of product integration with the demographic in question; thereby limiting their total probability and producing the levels of threat that they pose to Red Bull. Part 2: As has been stated previously, Red Bull did not initially seek to engage a costly marketing scheme as a means of promoting their beverage lines. Ins tead, they chose to sponsor key events and sporting activities that were regularly viewed in a positive light by their potential customers (Red Bull, 2013). However, as Red Bull’s fortunes of changed, they have been able to integrate with a higher degree of profitability and have been able to engage in celebrity marketing in the same means that much more powerful firms have done the same. In such a manner, as one might expect, Red Bull has been promoted and endorsed not necessarily by celebrities, but by sports stars. More specifically these sports stars cannot be understood upon the traditional lines of sports stars such as football players, basketball players, baseball players etc (Mortimer, 2012). Rather, they are extreme sports athletes that continue to engage with the brand image that has been discussed above. In such a manner, a few of these celebrity endorsers include the following: Blake Girffin, Rajon Rando, Reggie Bush, Shaun White, Bubba Stewart, Dallas Friday, Cas ey Kahne and Brian Vickers (Gorse, Chadwick, & Burton, 2010). This strategy, described above, has been extraordinarily beneficial to Red Bull as a means of continuing to int

Poor Communication within a Business Research Paper

Poor Communication within a Business - Research Paper Example Effects of poor communication to a business Ideally, for any business organization to succeed proper and effective communication becomes the backbone of this achievement. The effects of poor communication stream down from the organization’s top management organs to the least level of employees. The miscommunication may overflow to consumers in that the sales team may give minimized attention to the needs of their consumers hence delivering poor service to them. Essentially, the low morale of employees, in house miscommunication, non-content customers, and poor output or performance by staff becomes the product of poor communication. I. Low morale and motivation of employees Negative morale mothers animosity and harshness among staff members if their working environment is not fulfilling. In essence, the improper articulation of organizations goals and objectives to employees by the management translates to decreased morale. Sequentially, the general output by the employee’s decreases because of this inappropriate impact. Additionally, when team members do not have access to adequate information needed in the delegation of their tasks they lack motivation as they feel the need to work extra in order to fulfill their duties (Frater, 2003). Eventually, the working environment created is one characterized by bitter moods that end up spilling to the customer. In this regard, the top management needs to establish proper communication channels between them and their team players to ensure that their customers benefit from their services. A negative cycle may develop in the business, which may attract low sales and dismal performance by the business. Th e personnel become weak in the execution of tasks and implementation of the organization goals. Mainly, the whole idea of going in to a business undertaking is making a profit. Therefore, it will prove unworthy to continue venturing in a nonprofit able venture because of reasons that are preventable. In a counter approach, a business needs to ensure that the morale levels of its staff members are intact for the continued growth of a business. II. In house miscommunication and misinterpretation Subsequently, poor communication within a business setting has the ripple effect of compromising the in house

Compares and contrasts the interpretations of McClellans generalship Essay

Compares and contrasts the interpretations of McClellans generalship - Essay Example It is known that the common view in most books depict that the victory of the North in the Civil War is something inevitable due to mismanagement on the part of the South. Only few authors tackle the Civil War and the victory of the North in a perspective which emphasizes the North's dominance in terms of supplies, industrial infrastructure, and manpower. Thomas Rowland's George B. McClellan and Civil War History: In the Shadow of Grant and Sherman and James McPherson's Ordeal by Fire The Civil War and Reconstruction are two books which completely covers the Civil War and McClellan's generalship. Thus, it is interesting to know which information about George McClellan in the two books contradicts and which facts correspond with one another. Thomas Rowland's book revolves around George B. McClellan as a general and his contribution and role in the Civil War. Since the story revolves around him, the book covers his beginning--- from his previous work in the railroad to how he landed the position of a general in the Civil War. Initially, McClellan immediately attempted to get in touch with Winfield Scott, commander in chief of the American army, sending him several messages in which he suggested that the states between the Alleghenies and the Mississippi be organized as a military department under a head. On May 13, 1861, he received an order (dated May 3) appointing him to the command of the Department of the Ohio, consisting of Indiana, Ohio, and Illinois, with later additions of western Pennsylvania and western Virginia. On the other hand, McPherson's book tackles the Civil War as the focal point of the story, discussing only McClellan as one of the major contributors in the battle and North's victory. It covers all the facets of the war itself. Hence, the story covers the start of the Civil War which depicts the philosophical, social, political and economic political arguments that lead to the battle. Also, the book includes post-war events which include reuniting the nation and specifying the rights of the slaves from the South who have just gained freedom. In conclusion, the major difference between the two books is its approach on discussing the Civil War and McClellan's generalship. Rowland's work utilizes the inductive method of discussion as it focuses on McClellan while broadening the topic to the Civil War as it tackles McClellan's contribution to it. On the other hand, McPherson's work uses the deductive method ofdiscussion as its central subject is the Civil War and discussions of McClellan's generalship were only emphasized as the story narrates deductively from the Civil War to the figures who played important roles in it. Concerning McClellan's generalship, there are several points of agreement in the two books. Most importantly, both books confirm McClellan;s position as a general of the Department of the Ohio, which consists of Indiana, Ohio, and Illinois, Pennsylvania and Western Virginia and his contributions toward the Civil War. Also, the **other parts to follow Dec 31st, the

The Impact of Transformational Leadership On Organizational Innovation Research Paper

The Impact of Transformational Leadership On Organizational Innovation Moderated By Organizational Culture - Research Paper Example The changes in the global economy is yet another factor which is pressurizing the organizations as well as the leaders to develop and implement effective measures to ensure better and higher employee productivity, inspire innovation and create a favorable organizational environment and culture that supports and encourages employee creativity. Such transformations can be made through effective transformational leadership approach on the part of the management. There is documented evidence on the basis of various studies conducted over the years which point to the fact that transformational leadership plays a key role in bringing about revolutionary changes in the organizational environment and positively affects and influences various key areas such as: organizational productivity, employee creativity, increased job satisfaction, reduction in stress levels of employees and workers, greater levels of team commitment etc., among many others (Bass & Avolio, 1994; Bass, 1985; Dionne, Yamm arino, Atwater & Spangler, 2004; Howell & Avolio, 1993). Such studies suggest that transformational leadership can greatly influence and encourage organizational innovation and creativity as well as the development of appropriate and effective skills required to compete in this highly dynamic and ever changing external environment. There are various approaches to initiate and implement organizational change, however regardless of such approaches the key role in influencing such changes is played by the managers and leaders, who are required to influence and guide the employees through such a process. Organizations today are representative of a highly diverse... This essay stresses that the study of various theories and researches with regard to the impact of transformational leadership on organizational culture and innovation provide an insight into the role of leaders in managing change and influencing the employees to achieve higher performance outcomes. On the basis of the extensive research and studies carried out in this behalf, it can be safely claimed that transformational leadership has a direct impact on organizational innovation, culture, and vision. It instills various characteristic traits among the employees and followers such as a sense of commitment to team efforts. This paper makes a conclusion that furthermore studies and empirical research have pointed to the impact of transformational leaders on organizations in terms of building a strong and positive culture, indicating that such leadership style provides better opportunities to the leaders to influence their followers and building an environment which is effective in achieving the overall goals. The studies also suggest that there is a direct and positive relationship between transformational leaders and the organizational vision. The transformational leaders encourage innovation and provide a conducive environment to innovate and develop novel ideas to respond to the dynamic and rapidly changing external environment. Such a culture further helps in creation of new and long term visions for the organization which in turn helps it in sustaining its competitive positioning in the market by giving them a competitive edge.

Applied Linguistics - 1 Essay Example for Free

Applied Linguistics 1 Essay Language in literature is used to create alternatives to the real world. In doing so, the precise choice and ordering of words is very important. It not only creates a substitute world for us but also determines our attitude to its inhabitants and the events that take place there. This dependence upon precise wording is why a literary text loses so much in paraphrase or translation. However, despite this importance of precise wording, the meanings of literary works are often disturbingly imprecise. Apparently, the linguistics choices in literature are not the concern of applied linguistics. It does not have the same kind of direct social and economic consequences as language education policy, or the spread of English as lingua franca. Yet, it is wrong to decrease the value of the impact and importance of literature. It reflects our individual and social identities, embodies and criticizes the values of the society from which it comes, and it also has an important role to play in education. And because it is made fully from language, it has something to do applied linguistics. Literary stylistics :- Linguistic analysis can describe and analyze the language of a literary text but this is not an applied linguistic activity. However, It begins to move in that direction when linguistic choices are linked to their effects upon the reader. This is the attempt of literary stylistics. It is not in itself applied linguistics as it does not involve any practical decision making, but it is an important resource for the powerful and persuasive uses of language in general. It raises awareness of the importance of precise wording in addition to showing that there are more things in language use than the literal meaning of the words. Literary analysis cannot be brief in order to attain justice to its complex subject-matter. Stylistic analyses tend to highlight three related aspects of literary language: its deviation from the norms of everyday language use; its patterning of linguistic units to create rhythms, rhymes, and parallel constructions; and the ways in which the form of the words chosen seems to  intensify the meaning. These features of language use are not exclusive to literature. They characterize other highly valued uses of language such as prayer, song, and rhetoric. Generally, these features and other similar ones occur in emotive uses of language in society at large, whether in commercial, political, or interpersonal communication. Stylistic analyses can investigate the link between the forms of these language uses and their social and psychological power. If such analysis is used to discuss and reveal manipulation, it then becomes part of an applied linguistic process. Language and persuasion :- As language is used to tell the truth, it can also be used to distort facts, or to persuade people to take a particular stance towards them. Literary language partakes of this persuasive power. It manipulates our feelings and thoughts in ways which we accept happily. Other uses of language are unacceptable, seeking to control and influence our ideas in the service of some political or commercial interest. There are a big number of urgent issues in which language is used for manipulation such as; advertising, science, journals, even telephone operators speak from learned scripts. Applied linguistics should help understanding such issues. This is not only because the power of words is naturally interesting, but also because there are decisions to be made, often with far-reaching consequences for health, welfare, and success. Understanding linguistic techniques of persuasion can improve our ability to make rational judgments on which decisions making depends. Critical Discourse Analysis ( CDA ) :-  In fact, in any communication, there is selection and omission of information. For example, newspaper editors must choose which events to cover, how much space to give to each, and which facts to emphasize or omit. However, one cannot report any event or situation without selecting some facts in preference to others. But the selection reflects the values of the writer and the view of the world which he or she wishes to encourage in their readers. These matters are already apparent to the reader even without any specialize knowledge of language. What is more importance and interest to applied linguists is the presentation of the same facts in ways which, although telling the truth, affect the reader’s attitude. In literary texts, the wording is everything. For example, in the opening scenes of Macbeth, lady Macbeth says â€Å"what’s done is done†, and at the end in her lament she says â€Å"what’s done cannot be undone†. The literal meaning might be the same, but the effect is very different. The analysis of such details can be made to increase the people’s ability to read and listen critically, and to resist being manipulated by what is said. The analysis of such language and its effects is known as critical linguistics. When it is studied in a larger social context, it comes to be known as Critical Discourse Analysis ( CDA ). Another area of interest to applied linguistics is patterns of grammatical choice. For example, there are constructions which allow a speaker or writer not to mention the agent. Two strategies allow this to happen. One is passivization, the favoring of passive constructions over active ones. The other is nominalization, when actions and processes are referred to by nouns without mentioning the actual doers. The techniques can make an action seem certain and impersonal. The work of CDA specialists is of great social importance. Yet, they have the challenge of communicating their specialized knowledge to the outside world. To do this, they have to move in two opposite directions: one towards obfuscation and the other towards a false clarity. Obfuscation is the failure to speak as clearly as possible. The language of law and bureaucracy are often used as examples. It is claimed that in this case clarity should be sacrificed to exactness. The other direction is described as conversationalization and the creation of synthetic personality. This is the tendency for communication to be presented in the form of a casual conversation in which the relationship between the participants is apparently equal and intimate. This presents the opposite danger from obfuscation, for it may make matters simple and imprecise. There is a problem with CDA analyses which has been noted by several applied linguists. They focus their attention too much with the writer while deal too much passively with the reader. Most texts are both formed and interpreted in many different ways. The process of composition is often more hasty and specific purpose affair. Readings also are different. In short, there is a danger of assuming that understanding a text is fully determined by the language used.

Organ Donation Ethical Issues

Organ Donation Ethical Issues The need for the organ transplant is increasing in our sector of health care as more and more end stage diseases are being diagnosed. Organ transplantation may be a life-saving option, but they are not without their challenges and risks. The concept of organ transplantation is both miraculous and challenging at the same time. Whether a patient needs a new kidney, liver, heart, or lung, there are multiple issues that the patient and the family need to deal with. They involve decisions before the transplantation and medical issues postoperatively. An organ transplant bill that had been under study with the senate since 1992 was finally approved on 5 September 2007 as A Transplantation of Human Organs and Tissues Ordinance 2007 by the Government of Pakistan, and many illegal organ donation and transplantation centers were closed down and many senior doctors involved in the act were charged against it. The issue over here is much diversified and complex when we go into the details of the consequences of the act. Firstly, the question arises of what is right and what is permissible? Secondly, the right of making the laws for the right and wrong act is disputed and challenged by mankind, on the basis of his reasoning and self judgment. Moral Issues The organ transplantation has been long debated and addressed by many scholars from both religious and secular perspective. The major issues concerning the wide permissibility of the act are of bypassing the virtue ethics cardinal features: respect for autonomy, nonmaleficence, beneficence and justice. If we further categorize the ethical dilemmas we can address he organ transplant act under these broad types, which encompass their own challenges when it comes to making a sound and safe decision. These categories are: Transplant organ from a living person. Transplant of organ from a dead person Transplant from a fetus. If we were not being guided by the supreme law, which has been transedented on us, and let us believe, that man has the power of brains over all other logics and laws of nature. Then trying to find any solution for a given problem, or setting any rules to follow for any system to work would have been very difficult. In other words trying to find analogies for God grounded systems is beyond human competence and reasoning. Considering moral principles Considering the issue of organ donation and transplantation, the respect for autonomy is the right to choose for the decision making of certain biomedical ethical dilemma. It not just involves giving respect for the attitude, but also for the action to be performed. From pure secular ethics point, we can relate what Immanuel Kant had recognized from the concept of unconditional worth, stating that each individual has the capacity to determine his or her own moral destiny. To violate a persons autonomy is like treating that person merely as means, without regard to that persons own goals. Example if a person s dead and his organs are taken from his body without his previous advance directives of any such act, then, its again considered to be using that body as a means. But what if that organ was so precious in saving the life of a living person, who could have benefitted humanity if given a chance to live, e.g. a doctor or a well trained militant, etc. this shows the beneficence over the autonomy and serving the utilitarian ethical principle. If we consider the case of organ taken from a fetus, then again who is the ultimate supreme authority to give consent on behalf of that minor? What makes one decides the ruling of a certain act to be just for an individual? Then here comes the question of, who plays the role of the unquestionable evaluator and who among us is eligible to be devoid of all flaws in reasoning and decision making? Does the living donor has the ultimate right over his body or his relatives who have the right to decide the answer to this if another influential family member is the supposed recipient of the organ? A wife cannot take decision over her own medical issues without her husbands will and consent? A poor clan member of a certain tribe falls victim to the Jirga rulings. Similarly what happens to the war prisoners? The freedom fighters in occupied areas, who have been mutilated for organ trafficking? Who plays the role of just decision mak ing and for what principle? Is it justified that Greatest happiness Principle is fulfilled by the Utilitarian approach? Kantian approach, a duty to save human life? Egalitarian approach, to get equal benefit? Communitarian to serve the community benefits at the cost of ones own necessities and health. The questions remains open ended, if we try to rebut the argument with one ethical principle, then the other might get offended. Does virtue ethics answers every thing? Promoting Organ transplantation has three basic issues namely social, religious and political. The controversy still goes on whether to openly accept the permissibility of the act or to completely Bann it. Another important debate is on the issue of burial in case of cadaveric transplants. The question is of the sanctity of the deceased maintained at the time of burial if he is stripped off all his organs and a hollow coffin is buried instead; would any of us want such an end of life. Moreover some people are of the view that every individual holds the right to be buried as a whole and taking out his body organs (in cases when he hasnt left a clear will regarding the issue) despite in all good faith sounds unethical. These delicate and intricate details further complicate the allowance of this transplantation and organ donation act in full context in all diversities of cases. But the arguments strength depends upon careful analysis of each of the cases keeping in mind all kinds of ha rms and benefits ; be it physical, emotional or financial pertaining to the donor, recipient, and / or their families. Argumentative views regarding the retrieval of an organ from a cadaver as being a part of the corpse or not is also an aspect that cannot be overlooked. The controversial role of Advanced Directives has led to two main questions: 1. Does one have legal rights over ones body? 2. If that is the case, then what exactly is wrong with even selling something that belongs to me? Another view held by many individuals is that, so what it is just an organ? People can sell their organs, which is supposedly their ownership, to gain financial benefits for their families. This again holds the view of providing benefit to many, without doing harm(as the removal of organ is done under anesthesia). But doesnt this promotes the evil of organ trafficking which would harm many poor population and weaker ones in the society. This consequentionalist approach is again challenged here. The chain of this reaction would eventually affect many people, be it a good end or a bad. The principles of beneficence and nonmaleficence can be advanced in the context of different issues: like the expertise available, the disclosure of all the possible outcomes and complications of the procedure, for the donor and the recipient, both medical and financial. The support that would be needed by the family and the prognosis of such advanced procedures should be looked into detail to benefit the patient and do no harm to the donor and the family members. The professional may have an influential role on the decision making. The autonomy of the patient is usually surrogated by the financial and moral obligation of the social setup. There is a strong need for a system to keep a check on the medical problems of certain disease transmission through non screened donor organs, the use of unskilled surgeons in removing the organ, organ trafficking and selling, the actual financial damages of the post operative chemotherapy and potential need for the failure of the graft or re-transplantation, the actual life expectancy even after the transplant of individual case etc. Every states constitution differs in some aspect to their religious and cultural norms, example, what ever is permissible in Germany is not accepted in many Muslim states, so the need for a definite, supreme, sovereign law cannot be denied. Conclusion Finding the ultimate law which would be unchallengeable and flawless is yet to be defined by the human nature. The unlimited limits of transedental laws and reasoning begins, where my horizons of imagination and limited reasoning ends. The noble act of organ donation should be encouraged only in the limits drawn by the Shariah rulings of the contemporary times in view of its divines as an act of saving the humankind and helping those who are suffering. It should be given prime importance that these rulings certainly apply to variations of case selection as well.

Effects of Exercise on the Human Body

Effects of Exercise on the Human Body Exercise represents one the highest levels of extreme stresses to which the body can be exposed. Exercise physiology is the study of the function of the human body during various acute and chronic exercise conditions. These effects are significant during both short, high intensity exercise as well as with prolonged strenuous exercise such as done in endurance sports like marathons, ultramarathons, and road bicycle racing. In exercise, the liver generates extra glucose, while increased cardiovascular activity by the heart, and respiration by the lungs, provides an increased supply of oxygen. When exercise is very prolonged and strenuous, a decline, however, can occur in blood levels of glucose. In some individuals, this might even cause hypoglycemia and hypoxemia. There can also be cognitive and physical impairments due to dehydration. Another risk is low plasma sodium blood levels. Prolonged exercise is made possible by the human thermoregulation capacity to remove exercise waste hea t by sweat evaporation. This capacity evolved to enable early humans after many hours of persistence hunting to exhaust game animals that cannot remove so effectively exercise heat from their body. In general, the exercise-related measurements established for women follow the same general principles as those established for men, except for the quantitative differences caused by differences in body size, body composition, and levels of testosterone. In women, the values of muscle strength, pulmonary ventilation, and cardiac output (all variables related with muscle mass) are generally 60-75% of the exercise physiology values recorded in men. When measured in terms of strength per square centimeter, the female muscle can achieve the same force of contraction as that of a male. The functions of muscle tissues assume roles in homeostasis, as follows: Excitability Property of receiving and responding to stimuli such as the following: Neurotransmitters: Acetylcholine (ACh) stimulates skeletal muscle to contract, electrical stimuli: Applying electrical stimuli between cardiac and smooth muscle cells causes the muscles to contract, Applying a shock to skeletal muscle causes contraction, Hormonal stimuli: Oxytocin stimulates smooth muscle in the uterus to contract during labor.Contractility Ability to shorten. Extensibility Ability to stretch without damageElasticity Ability to return to original shape after extensionThrough contraction, muscle provides motion of the body (skeletal muscle), motion of blood (cardiac muscle), and motion of hollow organs such as the uterus, esophagus, stomach, intestines, and bladder (smooth muscle).Muscle tissue also helps maintain posture and produce heat. A large amount of body heat is produced by metabolism and by muscle con traction. Muscle contraction during shivering warms the body. Skeletal muscle consists of fibers (cells). These cells are up to 100 Â µm in diameter and often are as long as the muscle. Each contains sarcoplasm (cytoplasm) and multiple peripheral nuclei per fiber. Skeletal muscle is actually formed by the fusion of hundreds of embryonic cells. Other cell structures include the following:Each fiber is covered by a sarcolemma (plasma membrane). The sarcoplasmic reticulum (smooth endoplasmic reticulum) stores calcium, which is released into the sarcoplasm during muscle contraction. Transverse tubules (T tubules), which are extensions of the sarcolemma that penetrate cells, transmit electrical impulses from the sarcolemma inward, so electrical impulses penetrate deeply into the cell. Besides conducting electricity along their walls, T tubules contain extracellular fluid rich in glucose and oxygen.The sarcoplasm of fiber is rich in glycogen (glucose polymer) granules and myoglobin (oxygen-storing protein). It also is rich in mitochondria. Each fibe r contains hundreds to thousands of rodlike myofibrils, which are bundles of thin and thick protein chains termed myofilaments. From a cross-sectional view of a myofibril, each thick filament is surrounded by a hexagonal array of 6 thin filaments. Each thin filament is surrounded by a triangular array of thick filaments.myofilaments are composed of 3 proteins: actin, tropomyosin, and troponin. Thick myofilaments consist of bundles of approximately 200 myosin molecules. Myosin molecules look like double-headed golf clubs (both heads at the same end). The heads of the golf clubs are called myosin heads; they are also called cross-bridges because they link thick and thin filaments during contraction. They contain actin andadenosine triphosphate (ATP) binding sites. Myosin heads project out from the thick filaments, allowing them to bind to the thin filaments during contraction. Actin is a long chain of multiple globular proteins, similar in shape to kidney beans. Each globular subunit contains a myosin-binding site. Tropomyosin is a long strand of protein that covers the myosin-binding sites on actin when the muscle is relaxed. Troponin is a polypeptide complex that binds to tropomyosin, helping to position it over the myosin-binding sites on actin. During muscle contraction, calcium binds troponin, which causes tropomyosin to roll off of the myosin binding sites on actin. A muscle action potential travels over sarcolemma and enters the T tubules, causing the sarcoplasmic reticulum to release calcium into the sarcoplasm. This triggers the contractile process.Myosin cross-bridges pull on the actin myofilaments, causing the thin myofilaments of a sarcomere to slide toward the centers of the H zones.Deep fascia is a broad band of dense irregular connective tissue beneath and around muscle and organs. Deep fascia is different from superficial fascia, which is loose areolar connective tissue.Other connective-tissue components (all are extensions of deep fascia) include epimysium, which covers the entire muscle; perimysium, which penetrates into muscle and surrounds bundles of fibers called fascicles; and endomysium, which is delicate, barely visible, loose areolar tissue covering individual fibers (ie, individual cells).Tendons and aponeuroses are tough extensions of epimysium, perimysium, and endomysium. Tendons and aponeuroses are made of dense regular co nnective tissue and attach the muscle to bone or other muscle. Aponeuroses are broad, flat tendons. Tendon sheaths contain synovial fluid and enclose certain tendons. Tendon sheaths allow tendons to slide back and forth next to each other with lower friction. Tenosynovitis is inflammation of the tendon sheaths and tendons, especially those of the wrists, shoulders, and elbows. Tendons are not contractile and not very stretchy; furthermore, they are not very vascular and they heal poorly. Nerves convey impulses for muscular contraction. Nerves are bundles of nerve cell processes. Each nerve cell process (ie, axon) divides at its tip into a few to 10,000 branches called telodendria. At the end of each of these branches is an axon terminal that is rich in neurotransmitters.Blood provides nutrients and oxygen for contraction. An artery and a vein usually accompany a nerve that penetrates skeletal muscle. Arteries in muscles dilate during active muscular activity, thus increasing the supply of oxygen and glucose.A motor nerve is a bundle of axons that conducts nerve impulses away from the brain or spinal cord toward muscles. Each axon transmits an action potential (ie, nerve impulse), which is a burst of electricity. The nerve impulse travels along the axons at a steady rate, like fire travels along a fuse; however, nerve impulses travel extremely fast. Each axon has 4-2000 or more branches (ie, telodendria), with an average of 150 telodendria. Each separate branch suppli es a separate muscle cell. Thus, if an axon has 10 branches, it supplies 10 muscle fibers. Small motor units are for fine control of muscles; large motor units are for muscles that do not require such fine control.The neuromuscular junction is made of an axon terminal and the portion of the muscle fiber sarcolemma it nearly touches (called the motor endplate). The neurotransmitter released at the neuromuscular junction in skeletal muscle is ACh. The motor endplate is rich in thousands of ACh receptors; the receptors are integral proteins containing binding sites for ACh and sodium channels. Nerve impulse (action potential) reaches the axon terminal, which triggers calcium influx into the axon terminal.Calcium influx causes synaptic vesicles to release ACh via exocytosis. ACh diffuses across synaptic cleft.ACh binds to theACh receptor on the sarcolemma. Succinylcholine, a drug used to induce paralysis during surgery, binds to ACh receptors more tightly than ACh. Succinylcholine initially causes some depolarization, but then itbinds to the receptor, preventing ACh from binding. Therefore, it blocks the muscles stimulation by ACh, causing paralysis. Another drug that acts in a similar fashion is curare. These drugs do not cause pain relief or unconsciousness; thus, they are combined with other drugs during surgery. When ACh binds the receptor, it opens chemically regulated ion channels, which are sodium channels through the receptor molecule. Sodium, which is in high concentration outside cells and in low concentration inside cells, rushes into the cell through the channels.The cell, whose resting membrane potential along the inside of the membrane is negative when comparedwith the outside of the membrane, becomes positively charged along the inside of the membrane when sodium (a positive ion) rushes in. This change from a negative charge to a positive charge along the inner membrane is termed depolarization. The depolarization of one region of the sarcolemma (the motor endplate) initiates an action potential, which is a propagating wave of depolarization that travels (propagates) along the sarcolemma. Regions of membrane that become depolarized rapidly restore their proper ionic concentrations along their inner and outer surfaces in a process termed repolarization. (This process of depolarization, propagation, and repolarization is similar to dominoes that topple each other but also spring back into the upright position shortly afterward.)The action potential also propagates along the membrane lining the T tubules entering the cell. This action potential traveling along the T tubules causes the sarcoplasmic reticulum to release calcium into sarcoplasm.Calcium binds with troponin, causing it to pull on tropomyosin to change its or ientation, exposing myosin-binding sites on actin. An ATPase, which also functions as a myosin cross-bridging protein, splits ATP into adenosine diphosphate (ADP) + phosphate (P) in the previous contraction cycle. This energizes the myosin head. The energized myosin head, or cross-bridge, combines with myosin-binding sites on actin. Power stroke occurs. The attachment of the energized cross-bridge triggers a pivoting motion (ie, power stroke) of the myosin head. During the power stroke, ADP and P are released from the myosin cross-bridge. The power stroke causes thin actinmyofilaments to slide past thick myosin myofilaments toward the center of the A bands.ATP attaches to the myosin head again, allowing it to detach from actin. (In rigor mortis, an ATP deficiency occurs. Cross-bridges remain, and the muscles are rigid.)ATP is broken down to ADP and P, which cocks the myosin head again, preparing it to perform another power stroke if needed. Repeated detachment and reattachment of the cross-bridges results in shortening without much increase in tension during the shortening phase (isotonic contraction) or results in increased tension without shortening (isometric contraction).Release of the enzyme acetylcholinesterasein the neuromuscular junction destroys ACh and stops the generation of a muscle action potential. Calcium is taken back up (resequestered) in the sarcoplasmic reticulum, and myosin cross-bridges separate. ATP is required to separate myosin-actin cross-bridges. The muscle fiber resumes its resting state. The chemical energy that fuels muscular activities is ATP. For the first 5 or 6 seconds of muscle power, muscular activity can depend on the ATP that is already present in the muscle cells. Beyond this time, new amounts of ATP must be formed to enable the activation of muscular contractions that are needed to support longer and more vigorous physical activities. For activities that require a quick burst of energy that cannot be supplied by the ATP present in the muscle cells, the next 10-15 seconds of muscle power can be provided through the bodys use of the phosphagen system, which uses a substance called creatine phosphate to recycle ADP into ATP.4 For longer and more intense periods of physical activity, the body must rely on systems that break down the sugars (glucose) to produce ATP. The complete breakdown of glucose occurs in 2 ways: through anaerobic respiration (does not use oxygen) and through aerobic respiration (occurs in the presence of oxygen). The anaerobic use of gluco se to form ATP occurs as the body increases its muscle use beyond the capability of the phosphagen system to supply energy. In particular, the glycogen lactic acid system, through its anaerobic breakdown of glucose, provides approximately 30-40 seconds more of maximal muscle activity. For this system, each glucose molecule is split into 2 pyruvic acid molecules, and energy is released to form several ATP molecules, providing the extra energy. Then, the pyruvic acid partially breaks down further to produce lactic acid. If the lactic acid is allowed to accumulate in the muscle, one experiences muscle fatigue. At this point, the aerobic system must activate.The aerobic system in the body is used for sports that require an extensive and enduring expenditure of energy, such as a marathon race. Endurance sports absolutely require aerobic energy. A large amount of ATP must be provided to muscles to sustain the muscle power needed to perform such events without an excessive production of la ctic acid. This can only be accomplished when oxygen in the body is used to break down the pyruvic acid (that was produced anaerobically) into carbon dioxide, water, and energy by way of a very complex series of reactions known as the citric acid cycle. This cycle supports muscle usage for as long as the nutrients in the body last. The breakdown of pyruvic acid requires oxygen and slows or eliminates the accumulation of lactic acid. In summary, the 3 different muscle metabolic systems that supply the energy required for various activities are as follows: Phosphagen system (for 10- to 15-sec bursts of energy)Glycogen lactic acid system (for another 30-40 sec of energy)Aerobic system (provides a great deal of energy that is only limited by the bodys ability to supply oxygen and other important nutrients) Many sports require the use of a combination of these metabolic systems. By considering the vigor of a sports activity and its duration, one can estimate very closely which of the ene rgy systems are used for each activity. During muscular exercise, blood vessels in muscles dilate and blood flow is increased in order to increase the available oxygen supply. Up to a point, the available oxygen is sufficient to meet the energy needs of the body. However, when muscular exertion is very great, oxygen cannot be supplied to muscle fibers fast enough, and the aerobic breakdown of pyruvic acid cannot produce all the ATP required for further muscle contraction. During such periods, additional ATP is generated by anaerobic glycolysis. In the process, most of the pyruvic acid produced is converted to lactic acid. Although approximately 80% of the lactic acid diffuses from the skeletal muscles and is transported to the liver for conversion back to glucose or glycogen, some lactic acid accumulates in muscle tissue, making muscle contraction painful and causing fatigue. Ultimately, once adequate oxygen is available, lactic acid must be catabolized completely into carbon dioxide and water. After exercise has stopped, extra oxygen is required to metabolize lactic acid; to replenish ATP, phosphocreatine, and glycogen; and to replace (pay back) any oxygen that has been borrowed from hemoglobin, myoglobin (an iron-containing substance similar to hemoglobin that is found in muscle fibers), air in the lungs, and body fluids. The additional oxygen that must be taken into the body after vigorous exercise to restore all systems to their normal states is called oxygen debt. The debt is paid back by labored breathing that continues after exercise has stopped. Thus, the accumulation of lactic acid causes hard breathing and sufficient discomfort to stop muscle activity until homeostasis is restored.5 Eventually, muscle glycogen must also be restored. Restoration of muscle glycogen is accomplished through diet and may take several days, depending on the intensity of exercise. The maximum rate of oxygen consumption during the aerobic catabolism of pyruvic acid is called maximal oxygen uptake. Maximal oxygen uptake is determined by sex (higher in males), age (highest at approximately age 20 y), and size (increases with body size). Highly trained athletes can have maximal oxygen uptakes that are twice that of average people, probably owing to a combination of genetics and training. As a result, highly trained athletes are capable of greater muscular activity without increasing their lactic acid production and have lower oxygen debts, which is why they do not become short of breath as readily as untrained individuals. The best examples of light exercise are walking and light jogging. The muscles that are recruited during this type of exercise are those that contain a large amount of type I muscle cells, and, because these cells have a good blood supply, it is easy for fuels and oxygen to travel to the muscle. ATP consumption makes ADP available for new ATP synthesis. The presence of ADP (and the resulting synthesis of ATP) simulates the movement of hydrogen (H+) into the mitochondria; this, in turn, reduces the proton gradient and thus stimulates electron transport. The hydrogen on the reduced form of nicotinamide adenine dinucleotide (NADH) is used up, nicotinamide adenine dinucleotide (NAD) becomes available, and fatty acids and glucose are oxidized. Incidentally, the calcium released during contraction stimulates the enzymes in the Krebs cycle and stimulates the movement of the glucose transporter 4 (GLUT-4) from inside of the muscle cell to the cell membrane. Both these exercise-induced respon ses augment the elevation in fuel oxidation caused by the increase in ATP consumption. An increase in the pace of running simply results in an increased rate of fuel consumption, an increased fatty acid release, and, therefore, an increase in the rate of muscle fatty acid oxidation. However, if the intensity of the exercise increases even further, a stage is reached in which the rate of fatty acid oxidation becomes limited. The reasons why the rate of fatty acid oxidation reaches a maximum are not clear, but it is possible that the enzymes in the beta-oxidation pathway are saturated (ie, they reach a stage in which their maximal velocity [Vmax] is less than the rate of acetyl-coenzyme A [acetyl-CoA] consumption in the Krebs cycle). Alternatively, it may be that the availability of carnitine (the chemical required to transport the fatty acids into the mitochondria) becomes limited. Whatever the reason, the consequence is that as the pace rises, the demand for acetyl-CoA cannot be met by fatty acid oxidation alone. The accumulation of acetyl-CoA that was so effective at inhibiting the oxidation of glucose is no longer present, so pyruvate dehydrogenase starts working again and pyruvate is converted into acetyl-CoA. In other words, more of the glucose that enters the muscle cell is oxidized fully to carbon dioxide. Therefore, the energy used during moderate exercise is derived from a mixture of fatty acid and glucose oxidation. As the intensity of the exercise increases even further (ie, running at the pace of middle-distance races), the rate at which the muscles can extract glucose from the blood becomes limited. In other words, the rate of glucose transport reaches Vmax, either because the blood cannot supply the glucose fast enough or the number of GLUT-4s becomes limited. ATP generation cannot be serviced completely by exogenous fuels, and ATP levels decrease. Not only does this stimulate phosphofructokinase, it also stimulates glycogen phosphorylase. This me ans that glycogen stored within the muscle cells is broken down to provide glucose. Therefore, the fuel mix during strenuous exercise is composed of contributions from blood-borne glucose and fatty acids and from endogenously stored glycogen.Being fit (biochemically speaking) means that the individual has a well-developed cardiovascular system that can efficiently supply nutrients and oxygen to the muscles. Fit people have muscle cells that are well perfused with capillaries (ie, they have a good muscle blood supply). Their muscle cells also have a large number of mitochondria, and those mitochondria have a high activity of Krebs cycle enzymes, electron transport carriers, and oxidation enzymes. Individuals who are unfit must endure the consequences of a poorer blood supply, fewer mitochondria, less electron transport units, a lower activity of the Krebs cycle, and poorer activity of beta-oxidation enzymes. To generate ATP in the mitochondria, a steady supply of fuel and oxygen and decent activity of the oxidizing enzymes and carriers are needed. If any of these components are lacking, the rate at which ATP can be produced by mitochondria is compromised. Under these circumstances, the production of ATP by aerobic means is not sufficient to provide the muscles with sufficient ATP to sustain contractions. The result is anaerobic ATP generation using glycolysis. Increasing the flux through glycolysis but not increasing the oxidative consumption of the resulting pyruvate increases the production of lactate. The purpose of respiration is to provide oxygen to the tissues and to remove carbon dioxide from the tissues. To accomplish this, 4 major events must be regulated, as follows: Pulmonary ventilation. Diffusion of oxygen and carbon dioxide between the alveoli and the blood, Transport of oxygen and carbon dioxide in the blood and body fluids and to and from the cells, Regulation of ventilation and other aspects of respiration: Exercise causes these factors to change, but the body is designed to maintain homeostasisWhen one goes from a state of rest to a state of maximal intensity of exercise, oxygen consumption, carbon dioxide formation, and total pulmonary and alveolar ventilation increase by approximately 20-fold. A linear relationship exists between oxygen consumption and ventilation. At maximal exercise, pulmonary ventilation is 100-110 L/min, whereas maximal breathing capacity is 150-170 L/min. Thus, the maximal breathing capacity is approximately 50% greater than the actual pulmon ary ventilation during maximal exercise. This extra ventilation provides an element of safety that can be called on if the situation demands it (eg, at high altitudes, under hot conditions, abnormality in the respiratory system). Therefore, the respiratory system itself is not usually the most limiting factor in the delivery of oxygen to the muscles during maximal muscle aerobic metabolism. VO2 max is the rate of oxygen consumption under maximal aerobic metabolism. This rate in short-term studies is found to increase only 10% with the effect of training. However, that of a person who runs in marathons is 45% greater than that of an untrained person. This is believed to be partly genetically determined (eg, stronger respiratory muscles, larger chest size in relation to body size) and partly due to long-term training. Oxygen diffusing capacity is a measure of the rate at which oxygen can diffuse from the alveoli into the blood. An increase in diffusing capacity is observed in a state of maximal exercise. This results from the fact that blood flow through many of the pulmonary capillaries is sluggish in the resting state. In exercise, increased blood flow through the lungs causes all of the pulmonary capillaries to be perfused at their maximal level, providing a greater surface area through which oxygen can diffuse into the pulmonary capillary blood. Athletes who require greater amounts of oxygen per minute have been found to have higher diffusing capacities, but the exact reason why is not yet known. Although one would expect the oxygen pressure of arterial blood to decrease during strenuous exercise and carbon dioxide pressure of venous blood to increase far above normal, this is not the case. Both of these values remain close to normal. Stimulatory impulses from higher centers of the brain and from joint and muscle proprioceptive stimulatory reflexes account for the nervous stimulation of the respiratory and vasomotor center that provides almost exactly the pr oper increase in pulmonary ventilation to keep the blood respiratory gases almost normal. If nervous signals are too strong or weak, chemical factors bring about the final adjustment in respiration that is required to maintain homeostasis. Regular exercise makes the cardiovascular system more efficient at pumping blood and delivering oxygen to the exercise muscles. Releases of adrenaline and lactic acid into the blood result in an increase of the heart rate (HR). Basic definitions of terms are as follows:VO2 equals cardiac output times oxygen uptake necessary to supply oxygen to muscles. The Fick equation is the basis for determination of VO2. Exercises increase some of the different components of the cardiovascular system, such as stroke volume (SV), cardiac output, systolic blood pressure (BP), and mean arterial pressure. A greater percentage of the cardiac output goes to the exercising muscles. At rest, muscles receive approximately 20% of the total blood flow, but during exercise, the blood flow to muscles increases to 80-85%. To meet the metabolic demands of skeletal muscle during exercise, 2 major adjustments to blood flow must occur. First, cardiac output from the heart must increase. Second, blood flow from ina ctive organs and tissues must be redistributed to active skeletal muscle. Generally, the longer the duration of exercise, the greater the role the cardiovascular system plays in metabolism and performance during the exercise bout. An example would be the 100-meter sprint (little or no cardiovascular involvement) versus a marathon (maximal cardiovascular involvement). The cardiovascular system helps transport oxygen and nutrients to tissues, transport carbon dioxide and other metabolites to the lungs and kidneys, and distribute hormones throughout the body. The cardiovascular system also assists with thermoregulation.The pumping of blood by the heart requires the following 2 mechanisms to be efficient:Alternate periods of relaxation and contraction of the atria and ventriclesCoordinated opening and closing of the heart valves for unidirectional flow of blood The cardiac cycle is divided into 2 phases: ventricular diastole and ventricular systole.This phase begins with the opening of the atrioventricular (AV) valves. The mitral valve (located between the left atrium and left ventricle) opens when the left ventricular pressure falls below the left atrial pressure, and the blood from left atrium enters the left ventricle.Later, as the blood continues to flow into the left ventricle, the pressure in both chambers tends to equalize.At the end of the di astole, left atrial contractions cause an increase in left atrial pressure, thus again creating a pressure gradient between the left atrium and ventricle and forcing blood into the left ventricle.Ventricular systole begins with the contraction of the left ventricle, which is caused by the spread of an action potential over the left ventricle. The contraction of the left ventricle causes an increase in the left ventricular pressure. When this pressure is higher than the left atrial pressure, the mitral valve is closed abruptly.The left ventricular pressure continues to rise after the mitral valve is closed. When the left ventricular pressure rises above the pressure in the aorta, the aortic valve opens. This period between the closure of the mitral valve and the opening of the aortic valve is called isovolumetric contraction phase.The blood ejects out of the left ventricle and into the aorta once the aortic valve is opened. As the left ventricular contraction is continued, 2 processe s lead to a fall in the left ventricular pressure. These include a decrease in the strength of the ventricular contraction and a decrease in the volume of blood in the ventricle.When the left ventricular pressure falls below the aortic pressure, the aortic valve is closed. After the closure of the aortic valve, the left ventricular pressure falls rapidly as the left ventricle relaxes. When this pressure falls below the left atrial pressure, the mitral valve opens and allows blood to enter left ventricle. The period between the closure of the aortic valve closure and the opening of the mitral valve is called isovolumetric relaxation time. Right-sided heart chambers undergo the same phases simultaneously. Most of the work of the heart is completed when ventricular pressure exists. The greater the ventricular pressure, the greater the workload of the heart. Increases in BP dramatically increase the workload of the heart, and this is why hypertension is so harmful to the heart.Arterial BP is the pressure that is exerted against the walls of the vascular system. BP is determined by cardiac output and peripheral resistance. Arterial pressure can be estimated using a sphygmomanometer and a stethoscope. The reference range for males is 120/80 mm Hg; the reference range for females is 110/70 mm Hg. The difference between systolic and diastolic pressure is called the pulse pressure. The average pressure during a cardiac cycle is called the mean arterial pressure (MAP). MAP determines the rate of blood flow through the systemic circulation.During rest, MAP = diastolic BP + (0.33 X pulse pressure). For example, MAP = 80 + (0.33 X [120-80]), MAP = 93 mm Hg. During exercise, MAP = diastolic BP + (0.50 X pulse pressure). For example, MAP = 80 + (0.50 X [160-80]), MAP = 120 mm Hg. The heart has the ability to generate its own electrical activity, which is known as intrinsic rhythm. In the healthy heart, contraction is initiated in the sinoatrial (SA) node, which is often called the hearts pacemaker. If the SA node cannot set the rate, then other tissues in the heart are able to generate an electrical potential and establish the HR.The parasympathetic nervous system and the sympathetic nervous system affect a personsHR. Parasympathetic nervous system: The vagus nerve originates in the medulla and innervates the SA and AV nodes. The nerve releases ACh as the neurotransmitter. The response is a decrease in SA node and AV node activity, which causes a decrease in HR. Sympathetic nervous system: The nerves arise from the spinal cord and innervate the SA node and ventricular muscle mass. The nerves release norepinephrine as the neurotransmitter. The response is an increase in HR and a force of contraction of the ventricles.At rest, sympathetic and parasympathetic ne rvous stimulation are in balance. During exercise, parasympathetic stimulation decreases and sympathetic stimulation increases. Several factors can alter sympathetic nervous system input.Baroreceptors are groups of neurons located in the carotid arteries, the arch of aorta, and the right atrium. These neurons sense changes in pressure in the vascular system. An increase in BP results in an increase in parasympathetic activity except during exercise, when the sympathetic activity overrides the parasympathetic activity. Chemoreceptors are groups of neurons located in the arch of the aorta and the carotid arteries. These neurons sense changes in oxygen concentration. When oxygen concentration in the blood is decreased, parasympathetic activity decreasesand sympathetic activity increases. Temperature receptors are neurons located throughout the body. These neurons are sensitive to changes in body temperature. As temperature increases, sympathetic activity increases to cool Effects of Exercise on the Human Body Effects of Exercise on the Human Body Exercise represents one the highest levels of extreme stresses to which the body can be exposed. Exercise physiology is the study of the function of the human body during various acute and chronic exercise conditions. These effects are significant during both short, high intensity exercise as well as with prolonged strenuous exercise such as done in endurance sports like marathons, ultramarathons, and road bicycle racing. In exercise, the liver generates extra glucose, while increased cardiovascular activity by the heart, and respiration by the lungs, provides an increased supply of oxygen. When exercise is very prolonged and strenuous, a decline, however, can occur in blood levels of glucose. In some individuals, this might even cause hypoglycemia and hypoxemia. There can also be cognitive and physical impairments due to dehydration. Another risk is low plasma sodium blood levels. Prolonged exercise is made possible by the human thermoregulation capacity to remove exercise waste hea t by sweat evaporation. This capacity evolved to enable early humans after many hours of persistence hunting to exhaust game animals that cannot remove so effectively exercise heat from their body. In general, the exercise-related measurements established for women follow the same general principles as those established for men, except for the quantitative differences caused by differences in body size, body composition, and levels of testosterone. In women, the values of muscle strength, pulmonary ventilation, and cardiac output (all variables related with muscle mass) are generally 60-75% of the exercise physiology values recorded in men. When measured in terms of strength per square centimeter, the female muscle can achieve the same force of contraction as that of a male. The functions of muscle tissues assume roles in homeostasis, as follows: Excitability Property of receiving and responding to stimuli such as the following: Neurotransmitters: Acetylcholine (ACh) stimulates skeletal muscle to contract, electrical stimuli: Applying electrical stimuli between cardiac and smooth muscle cells causes the muscles to contract, Applying a shock to skeletal muscle causes contraction, Hormonal stimuli: Oxytocin stimulates smooth muscle in the uterus to contract during labor.Contractility Ability to shorten. Extensibility Ability to stretch without damageElasticity Ability to return to original shape after extensionThrough contraction, muscle provides motion of the body (skeletal muscle), motion of blood (cardiac muscle), and motion of hollow organs such as the uterus, esophagus, stomach, intestines, and bladder (smooth muscle).Muscle tissue also helps maintain posture and produce heat. A large amount of body heat is produced by metabolism and by muscle con traction. Muscle contraction during shivering warms the body. Skeletal muscle consists of fibers (cells). These cells are up to 100 Â µm in diameter and often are as long as the muscle. Each contains sarcoplasm (cytoplasm) and multiple peripheral nuclei per fiber. Skeletal muscle is actually formed by the fusion of hundreds of embryonic cells. Other cell structures include the following:Each fiber is covered by a sarcolemma (plasma membrane). The sarcoplasmic reticulum (smooth endoplasmic reticulum) stores calcium, which is released into the sarcoplasm during muscle contraction. Transverse tubules (T tubules), which are extensions of the sarcolemma that penetrate cells, transmit electrical impulses from the sarcolemma inward, so electrical impulses penetrate deeply into the cell. Besides conducting electricity along their walls, T tubules contain extracellular fluid rich in glucose and oxygen.The sarcoplasm of fiber is rich in glycogen (glucose polymer) granules and myoglobin (oxygen-storing protein). It also is rich in mitochondria. Each fibe r contains hundreds to thousands of rodlike myofibrils, which are bundles of thin and thick protein chains termed myofilaments. From a cross-sectional view of a myofibril, each thick filament is surrounded by a hexagonal array of 6 thin filaments. Each thin filament is surrounded by a triangular array of thick filaments.myofilaments are composed of 3 proteins: actin, tropomyosin, and troponin. Thick myofilaments consist of bundles of approximately 200 myosin molecules. Myosin molecules look like double-headed golf clubs (both heads at the same end). The heads of the golf clubs are called myosin heads; they are also called cross-bridges because they link thick and thin filaments during contraction. They contain actin andadenosine triphosphate (ATP) binding sites. Myosin heads project out from the thick filaments, allowing them to bind to the thin filaments during contraction. Actin is a long chain of multiple globular proteins, similar in shape to kidney beans. Each globular subunit contains a myosin-binding site. Tropomyosin is a long strand of protein that covers the myosin-binding sites on actin when the muscle is relaxed. Troponin is a polypeptide complex that binds to tropomyosin, helping to position it over the myosin-binding sites on actin. During muscle contraction, calcium binds troponin, which causes tropomyosin to roll off of the myosin binding sites on actin. A muscle action potential travels over sarcolemma and enters the T tubules, causing the sarcoplasmic reticulum to release calcium into the sarcoplasm. This triggers the contractile process.Myosin cross-bridges pull on the actin myofilaments, causing the thin myofilaments of a sarcomere to slide toward the centers of the H zones.Deep fascia is a broad band of dense irregular connective tissue beneath and around muscle and organs. Deep fascia is different from superficial fascia, which is loose areolar connective tissue.Other connective-tissue components (all are extensions of deep fascia) include epimysium, which covers the entire muscle; perimysium, which penetrates into muscle and surrounds bundles of fibers called fascicles; and endomysium, which is delicate, barely visible, loose areolar tissue covering individual fibers (ie, individual cells).Tendons and aponeuroses are tough extensions of epimysium, perimysium, and endomysium. Tendons and aponeuroses are made of dense regular co nnective tissue and attach the muscle to bone or other muscle. Aponeuroses are broad, flat tendons. Tendon sheaths contain synovial fluid and enclose certain tendons. Tendon sheaths allow tendons to slide back and forth next to each other with lower friction. Tenosynovitis is inflammation of the tendon sheaths and tendons, especially those of the wrists, shoulders, and elbows. Tendons are not contractile and not very stretchy; furthermore, they are not very vascular and they heal poorly. Nerves convey impulses for muscular contraction. Nerves are bundles of nerve cell processes. Each nerve cell process (ie, axon) divides at its tip into a few to 10,000 branches called telodendria. At the end of each of these branches is an axon terminal that is rich in neurotransmitters.Blood provides nutrients and oxygen for contraction. An artery and a vein usually accompany a nerve that penetrates skeletal muscle. Arteries in muscles dilate during active muscular activity, thus increasing the supply of oxygen and glucose.A motor nerve is a bundle of axons that conducts nerve impulses away from the brain or spinal cord toward muscles. Each axon transmits an action potential (ie, nerve impulse), which is a burst of electricity. The nerve impulse travels along the axons at a steady rate, like fire travels along a fuse; however, nerve impulses travel extremely fast. Each axon has 4-2000 or more branches (ie, telodendria), with an average of 150 telodendria. Each separate branch suppli es a separate muscle cell. Thus, if an axon has 10 branches, it supplies 10 muscle fibers. Small motor units are for fine control of muscles; large motor units are for muscles that do not require such fine control.The neuromuscular junction is made of an axon terminal and the portion of the muscle fiber sarcolemma it nearly touches (called the motor endplate). The neurotransmitter released at the neuromuscular junction in skeletal muscle is ACh. The motor endplate is rich in thousands of ACh receptors; the receptors are integral proteins containing binding sites for ACh and sodium channels. Nerve impulse (action potential) reaches the axon terminal, which triggers calcium influx into the axon terminal.Calcium influx causes synaptic vesicles to release ACh via exocytosis. ACh diffuses across synaptic cleft.ACh binds to theACh receptor on the sarcolemma. Succinylcholine, a drug used to induce paralysis during surgery, binds to ACh receptors more tightly than ACh. Succinylcholine initially causes some depolarization, but then itbinds to the receptor, preventing ACh from binding. Therefore, it blocks the muscles stimulation by ACh, causing paralysis. Another drug that acts in a similar fashion is curare. These drugs do not cause pain relief or unconsciousness; thus, they are combined with other drugs during surgery. When ACh binds the receptor, it opens chemically regulated ion channels, which are sodium channels through the receptor molecule. Sodium, which is in high concentration outside cells and in low concentration inside cells, rushes into the cell through the channels.The cell, whose resting membrane potential along the inside of the membrane is negative when comparedwith the outside of the membrane, becomes positively charged along the inside of the membrane when sodium (a positive ion) rushes in. This change from a negative charge to a positive charge along the inner membrane is termed depolarization. The depolarization of one region of the sarcolemma (the motor endplate) initiates an action potential, which is a propagating wave of depolarization that travels (propagates) along the sarcolemma. Regions of membrane that become depolarized rapidly restore their proper ionic concentrations along their inner and outer surfaces in a process termed repolarization. (This process of depolarization, propagation, and repolarization is similar to dominoes that topple each other but also spring back into the upright position shortly afterward.)The action potential also propagates along the membrane lining the T tubules entering the cell. This action potential traveling along the T tubules causes the sarcoplasmic reticulum to release calcium into sarcoplasm.Calcium binds with troponin, causing it to pull on tropomyosin to change its or ientation, exposing myosin-binding sites on actin. An ATPase, which also functions as a myosin cross-bridging protein, splits ATP into adenosine diphosphate (ADP) + phosphate (P) in the previous contraction cycle. This energizes the myosin head. The energized myosin head, or cross-bridge, combines with myosin-binding sites on actin. Power stroke occurs. The attachment of the energized cross-bridge triggers a pivoting motion (ie, power stroke) of the myosin head. During the power stroke, ADP and P are released from the myosin cross-bridge. The power stroke causes thin actinmyofilaments to slide past thick myosin myofilaments toward the center of the A bands.ATP attaches to the myosin head again, allowing it to detach from actin. (In rigor mortis, an ATP deficiency occurs. Cross-bridges remain, and the muscles are rigid.)ATP is broken down to ADP and P, which cocks the myosin head again, preparing it to perform another power stroke if needed. Repeated detachment and reattachment of the cross-bridges results in shortening without much increase in tension during the shortening phase (isotonic contraction) or results in increased tension without shortening (isometric contraction).Release of the enzyme acetylcholinesterasein the neuromuscular junction destroys ACh and stops the generation of a muscle action potential. Calcium is taken back up (resequestered) in the sarcoplasmic reticulum, and myosin cross-bridges separate. ATP is required to separate myosin-actin cross-bridges. The muscle fiber resumes its resting state. The chemical energy that fuels muscular activities is ATP. For the first 5 or 6 seconds of muscle power, muscular activity can depend on the ATP that is already present in the muscle cells. Beyond this time, new amounts of ATP must be formed to enable the activation of muscular contractions that are needed to support longer and more vigorous physical activities. For activities that require a quick burst of energy that cannot be supplied by the ATP present in the muscle cells, the next 10-15 seconds of muscle power can be provided through the bodys use of the phosphagen system, which uses a substance called creatine phosphate to recycle ADP into ATP.4 For longer and more intense periods of physical activity, the body must rely on systems that break down the sugars (glucose) to produce ATP. The complete breakdown of glucose occurs in 2 ways: through anaerobic respiration (does not use oxygen) and through aerobic respiration (occurs in the presence of oxygen). The anaerobic use of gluco se to form ATP occurs as the body increases its muscle use beyond the capability of the phosphagen system to supply energy. In particular, the glycogen lactic acid system, through its anaerobic breakdown of glucose, provides approximately 30-40 seconds more of maximal muscle activity. For this system, each glucose molecule is split into 2 pyruvic acid molecules, and energy is released to form several ATP molecules, providing the extra energy. Then, the pyruvic acid partially breaks down further to produce lactic acid. If the lactic acid is allowed to accumulate in the muscle, one experiences muscle fatigue. At this point, the aerobic system must activate.The aerobic system in the body is used for sports that require an extensive and enduring expenditure of energy, such as a marathon race. Endurance sports absolutely require aerobic energy. A large amount of ATP must be provided to muscles to sustain the muscle power needed to perform such events without an excessive production of la ctic acid. This can only be accomplished when oxygen in the body is used to break down the pyruvic acid (that was produced anaerobically) into carbon dioxide, water, and energy by way of a very complex series of reactions known as the citric acid cycle. This cycle supports muscle usage for as long as the nutrients in the body last. The breakdown of pyruvic acid requires oxygen and slows or eliminates the accumulation of lactic acid. In summary, the 3 different muscle metabolic systems that supply the energy required for various activities are as follows: Phosphagen system (for 10- to 15-sec bursts of energy)Glycogen lactic acid system (for another 30-40 sec of energy)Aerobic system (provides a great deal of energy that is only limited by the bodys ability to supply oxygen and other important nutrients) Many sports require the use of a combination of these metabolic systems. By considering the vigor of a sports activity and its duration, one can estimate very closely which of the ene rgy systems are used for each activity. During muscular exercise, blood vessels in muscles dilate and blood flow is increased in order to increase the available oxygen supply. Up to a point, the available oxygen is sufficient to meet the energy needs of the body. However, when muscular exertion is very great, oxygen cannot be supplied to muscle fibers fast enough, and the aerobic breakdown of pyruvic acid cannot produce all the ATP required for further muscle contraction. During such periods, additional ATP is generated by anaerobic glycolysis. In the process, most of the pyruvic acid produced is converted to lactic acid. Although approximately 80% of the lactic acid diffuses from the skeletal muscles and is transported to the liver for conversion back to glucose or glycogen, some lactic acid accumulates in muscle tissue, making muscle contraction painful and causing fatigue. Ultimately, once adequate oxygen is available, lactic acid must be catabolized completely into carbon dioxide and water. After exercise has stopped, extra oxygen is required to metabolize lactic acid; to replenish ATP, phosphocreatine, and glycogen; and to replace (pay back) any oxygen that has been borrowed from hemoglobin, myoglobin (an iron-containing substance similar to hemoglobin that is found in muscle fibers), air in the lungs, and body fluids. The additional oxygen that must be taken into the body after vigorous exercise to restore all systems to their normal states is called oxygen debt. The debt is paid back by labored breathing that continues after exercise has stopped. Thus, the accumulation of lactic acid causes hard breathing and sufficient discomfort to stop muscle activity until homeostasis is restored.5 Eventually, muscle glycogen must also be restored. Restoration of muscle glycogen is accomplished through diet and may take several days, depending on the intensity of exercise. The maximum rate of oxygen consumption during the aerobic catabolism of pyruvic acid is called maximal oxygen uptake. Maximal oxygen uptake is determined by sex (higher in males), age (highest at approximately age 20 y), and size (increases with body size). Highly trained athletes can have maximal oxygen uptakes that are twice that of average people, probably owing to a combination of genetics and training. As a result, highly trained athletes are capable of greater muscular activity without increasing their lactic acid production and have lower oxygen debts, which is why they do not become short of breath as readily as untrained individuals. The best examples of light exercise are walking and light jogging. The muscles that are recruited during this type of exercise are those that contain a large amount of type I muscle cells, and, because these cells have a good blood supply, it is easy for fuels and oxygen to travel to the muscle. ATP consumption makes ADP available for new ATP synthesis. The presence of ADP (and the resulting synthesis of ATP) simulates the movement of hydrogen (H+) into the mitochondria; this, in turn, reduces the proton gradient and thus stimulates electron transport. The hydrogen on the reduced form of nicotinamide adenine dinucleotide (NADH) is used up, nicotinamide adenine dinucleotide (NAD) becomes available, and fatty acids and glucose are oxidized. Incidentally, the calcium released during contraction stimulates the enzymes in the Krebs cycle and stimulates the movement of the glucose transporter 4 (GLUT-4) from inside of the muscle cell to the cell membrane. Both these exercise-induced respon ses augment the elevation in fuel oxidation caused by the increase in ATP consumption. An increase in the pace of running simply results in an increased rate of fuel consumption, an increased fatty acid release, and, therefore, an increase in the rate of muscle fatty acid oxidation. However, if the intensity of the exercise increases even further, a stage is reached in which the rate of fatty acid oxidation becomes limited. The reasons why the rate of fatty acid oxidation reaches a maximum are not clear, but it is possible that the enzymes in the beta-oxidation pathway are saturated (ie, they reach a stage in which their maximal velocity [Vmax] is less than the rate of acetyl-coenzyme A [acetyl-CoA] consumption in the Krebs cycle). Alternatively, it may be that the availability of carnitine (the chemical required to transport the fatty acids into the mitochondria) becomes limited. Whatever the reason, the consequence is that as the pace rises, the demand for acetyl-CoA cannot be met by fatty acid oxidation alone. The accumulation of acetyl-CoA that was so effective at inhibiting the oxidation of glucose is no longer present, so pyruvate dehydrogenase starts working again and pyruvate is converted into acetyl-CoA. In other words, more of the glucose that enters the muscle cell is oxidized fully to carbon dioxide. Therefore, the energy used during moderate exercise is derived from a mixture of fatty acid and glucose oxidation. As the intensity of the exercise increases even further (ie, running at the pace of middle-distance races), the rate at which the muscles can extract glucose from the blood becomes limited. In other words, the rate of glucose transport reaches Vmax, either because the blood cannot supply the glucose fast enough or the number of GLUT-4s becomes limited. ATP generation cannot be serviced completely by exogenous fuels, and ATP levels decrease. Not only does this stimulate phosphofructokinase, it also stimulates glycogen phosphorylase. This me ans that glycogen stored within the muscle cells is broken down to provide glucose. Therefore, the fuel mix during strenuous exercise is composed of contributions from blood-borne glucose and fatty acids and from endogenously stored glycogen.Being fit (biochemically speaking) means that the individual has a well-developed cardiovascular system that can efficiently supply nutrients and oxygen to the muscles. Fit people have muscle cells that are well perfused with capillaries (ie, they have a good muscle blood supply). Their muscle cells also have a large number of mitochondria, and those mitochondria have a high activity of Krebs cycle enzymes, electron transport carriers, and oxidation enzymes. Individuals who are unfit must endure the consequences of a poorer blood supply, fewer mitochondria, less electron transport units, a lower activity of the Krebs cycle, and poorer activity of beta-oxidation enzymes. To generate ATP in the mitochondria, a steady supply of fuel and oxygen and decent activity of the oxidizing enzymes and carriers are needed. If any of these components are lacking, the rate at which ATP can be produced by mitochondria is compromised. Under these circumstances, the production of ATP by aerobic means is not sufficient to provide the muscles with sufficient ATP to sustain contractions. The result is anaerobic ATP generation using glycolysis. Increasing the flux through glycolysis but not increasing the oxidative consumption of the resulting pyruvate increases the production of lactate. The purpose of respiration is to provide oxygen to the tissues and to remove carbon dioxide from the tissues. To accomplish this, 4 major events must be regulated, as follows: Pulmonary ventilation. Diffusion of oxygen and carbon dioxide between the alveoli and the blood, Transport of oxygen and carbon dioxide in the blood and body fluids and to and from the cells, Regulation of ventilation and other aspects of respiration: Exercise causes these factors to change, but the body is designed to maintain homeostasisWhen one goes from a state of rest to a state of maximal intensity of exercise, oxygen consumption, carbon dioxide formation, and total pulmonary and alveolar ventilation increase by approximately 20-fold. A linear relationship exists between oxygen consumption and ventilation. At maximal exercise, pulmonary ventilation is 100-110 L/min, whereas maximal breathing capacity is 150-170 L/min. Thus, the maximal breathing capacity is approximately 50% greater than the actual pulmon ary ventilation during maximal exercise. This extra ventilation provides an element of safety that can be called on if the situation demands it (eg, at high altitudes, under hot conditions, abnormality in the respiratory system). Therefore, the respiratory system itself is not usually the most limiting factor in the delivery of oxygen to the muscles during maximal muscle aerobic metabolism. VO2 max is the rate of oxygen consumption under maximal aerobic metabolism. This rate in short-term studies is found to increase only 10% with the effect of training. However, that of a person who runs in marathons is 45% greater than that of an untrained person. This is believed to be partly genetically determined (eg, stronger respiratory muscles, larger chest size in relation to body size) and partly due to long-term training. Oxygen diffusing capacity is a measure of the rate at which oxygen can diffuse from the alveoli into the blood. An increase in diffusing capacity is observed in a state of maximal exercise. This results from the fact that blood flow through many of the pulmonary capillaries is sluggish in the resting state. In exercise, increased blood flow through the lungs causes all of the pulmonary capillaries to be perfused at their maximal level, providing a greater surface area through which oxygen can diffuse into the pulmonary capillary blood. Athletes who require greater amounts of oxygen per minute have been found to have higher diffusing capacities, but the exact reason why is not yet known. Although one would expect the oxygen pressure of arterial blood to decrease during strenuous exercise and carbon dioxide pressure of venous blood to increase far above normal, this is not the case. Both of these values remain close to normal. Stimulatory impulses from higher centers of the brain and from joint and muscle proprioceptive stimulatory reflexes account for the nervous stimulation of the respiratory and vasomotor center that provides almost exactly the pr oper increase in pulmonary ventilation to keep the blood respiratory gases almost normal. If nervous signals are too strong or weak, chemical factors bring about the final adjustment in respiration that is required to maintain homeostasis. Regular exercise makes the cardiovascular system more efficient at pumping blood and delivering oxygen to the exercise muscles. Releases of adrenaline and lactic acid into the blood result in an increase of the heart rate (HR). Basic definitions of terms are as follows:VO2 equals cardiac output times oxygen uptake necessary to supply oxygen to muscles. The Fick equation is the basis for determination of VO2. Exercises increase some of the different components of the cardiovascular system, such as stroke volume (SV), cardiac output, systolic blood pressure (BP), and mean arterial pressure. A greater percentage of the cardiac output goes to the exercising muscles. At rest, muscles receive approximately 20% of the total blood flow, but during exercise, the blood flow to muscles increases to 80-85%. To meet the metabolic demands of skeletal muscle during exercise, 2 major adjustments to blood flow must occur. First, cardiac output from the heart must increase. Second, blood flow from ina ctive organs and tissues must be redistributed to active skeletal muscle. Generally, the longer the duration of exercise, the greater the role the cardiovascular system plays in metabolism and performance during the exercise bout. An example would be the 100-meter sprint (little or no cardiovascular involvement) versus a marathon (maximal cardiovascular involvement). The cardiovascular system helps transport oxygen and nutrients to tissues, transport carbon dioxide and other metabolites to the lungs and kidneys, and distribute hormones throughout the body. The cardiovascular system also assists with thermoregulation.The pumping of blood by the heart requires the following 2 mechanisms to be efficient:Alternate periods of relaxation and contraction of the atria and ventriclesCoordinated opening and closing of the heart valves for unidirectional flow of blood The cardiac cycle is divided into 2 phases: ventricular diastole and ventricular systole.This phase begins with the opening of the atrioventricular (AV) valves. The mitral valve (located between the left atrium and left ventricle) opens when the left ventricular pressure falls below the left atrial pressure, and the blood from left atrium enters the left ventricle.Later, as the blood continues to flow into the left ventricle, the pressure in both chambers tends to equalize.At the end of the di astole, left atrial contractions cause an increase in left atrial pressure, thus again creating a pressure gradient between the left atrium and ventricle and forcing blood into the left ventricle.Ventricular systole begins with the contraction of the left ventricle, which is caused by the spread of an action potential over the left ventricle. The contraction of the left ventricle causes an increase in the left ventricular pressure. When this pressure is higher than the left atrial pressure, the mitral valve is closed abruptly.The left ventricular pressure continues to rise after the mitral valve is closed. When the left ventricular pressure rises above the pressure in the aorta, the aortic valve opens. This period between the closure of the mitral valve and the opening of the aortic valve is called isovolumetric contraction phase.The blood ejects out of the left ventricle and into the aorta once the aortic valve is opened. As the left ventricular contraction is continued, 2 processe s lead to a fall in the left ventricular pressure. These include a decrease in the strength of the ventricular contraction and a decrease in the volume of blood in the ventricle.When the left ventricular pressure falls below the aortic pressure, the aortic valve is closed. After the closure of the aortic valve, the left ventricular pressure falls rapidly as the left ventricle relaxes. When this pressure falls below the left atrial pressure, the mitral valve opens and allows blood to enter left ventricle. The period between the closure of the aortic valve closure and the opening of the mitral valve is called isovolumetric relaxation time. Right-sided heart chambers undergo the same phases simultaneously. Most of the work of the heart is completed when ventricular pressure exists. The greater the ventricular pressure, the greater the workload of the heart. Increases in BP dramatically increase the workload of the heart, and this is why hypertension is so harmful to the heart.Arterial BP is the pressure that is exerted against the walls of the vascular system. BP is determined by cardiac output and peripheral resistance. Arterial pressure can be estimated using a sphygmomanometer and a stethoscope. The reference range for males is 120/80 mm Hg; the reference range for females is 110/70 mm Hg. The difference between systolic and diastolic pressure is called the pulse pressure. The average pressure during a cardiac cycle is called the mean arterial pressure (MAP). MAP determines the rate of blood flow through the systemic circulation.During rest, MAP = diastolic BP + (0.33 X pulse pressure). For example, MAP = 80 + (0.33 X [120-80]), MAP = 93 mm Hg. During exercise, MAP = diastolic BP + (0.50 X pulse pressure). For example, MAP = 80 + (0.50 X [160-80]), MAP = 120 mm Hg. The heart has the ability to generate its own electrical activity, which is known as intrinsic rhythm. In the healthy heart, contraction is initiated in the sinoatrial (SA) node, which is often called the hearts pacemaker. If the SA node cannot set the rate, then other tissues in the heart are able to generate an electrical potential and establish the HR.The parasympathetic nervous system and the sympathetic nervous system affect a personsHR. Parasympathetic nervous system: The vagus nerve originates in the medulla and innervates the SA and AV nodes. The nerve releases ACh as the neurotransmitter. The response is a decrease in SA node and AV node activity, which causes a decrease in HR. Sympathetic nervous system: The nerves arise from the spinal cord and innervate the SA node and ventricular muscle mass. The nerves release norepinephrine as the neurotransmitter. The response is an increase in HR and a force of contraction of the ventricles.At rest, sympathetic and parasympathetic ne rvous stimulation are in balance. During exercise, parasympathetic stimulation decreases and sympathetic stimulation increases. Several factors can alter sympathetic nervous system input.Baroreceptors are groups of neurons located in the carotid arteries, the arch of aorta, and the right atrium. These neurons sense changes in pressure in the vascular system. An increase in BP results in an increase in parasympathetic activity except during exercise, when the sympathetic activity overrides the parasympathetic activity. Chemoreceptors are groups of neurons located in the arch of the aorta and the carotid arteries. These neurons sense changes in oxygen concentration. When oxygen concentration in the blood is decreased, parasympathetic activity decreasesand sympathetic activity increases. Temperature receptors are neurons located throughout the body. These neurons are sensitive to changes in body temperature. As temperature increases, sympathetic activity increases to cool