我们都知道咖啡因具有刺激作用,你知道咖啡因对提高运动成绩有帮助吗?来看看下面的文章是怎么说的
Though it used to get a bad rap, caffeine is now linked to a variety of health bonuses like preventing type II diabetes and Parkinson’s disease, speeding up metabolism, and easing headaches. As they do with most anything that offers the opportunity for better performance, athletes have started chugging caffeine-enhanced sports drinks and gels, looking for a safe and legal way to enhance endurance.
But does caffeine really do all that much for athletic performance, or is there a placebo effect at work here? Do caffeine’s benefits outweigh its potential risks? And how much is too much?
The Most Widely Used Drug
Almost everyone ingests caffeine at some point in their lives, and most do it regularly. It’s everywhere: in coffee, tea, colas, chocolate, and as a naturally occurring substance in many plants. Because its use is so widespread, the World Anti-Doping Agency removed caffeine from its list of banned substances in January 2004. The Agency has frequently threatened to restore caffeine to the list since then, but has not done so.
Anyone who makes the daily Starbuck’s run (or two, or five) is familiar with the ways in which caffeine acts on the central nervous system (CNS) to reduce fatigue and pain perception, improve mental acuity, and improve endurance.
We know that our morning cuppa joe keeps us sharp and alert at work, but what does it really do for us on the track? Most sports scientists agree that caffeine really does have ergogenic (performance-enhancing) benefits, but they disagree on the nature of those benefits, and how best to reap them.
According to Dr. Mark Tarnopolsky of McMaster University in Canada, it is “unequivocal that caffeine improves performance,” but it may do so through a different mechanism than researchers previously thought. Rather than encourage muscles to use fat as fuel instead of glycogen, as old school science would have it, sports experts now believe that caffeine releases calcium stored in muscles and affects the brain’s sense of exhaustion.
In other words, caffeine doesn’t really enhance high intensity athletic performance so much as restore it. You won’t really be able to run harder, although it might feel that way; but you’ll be able to maintain your peak performance for a longer period of time.
The Law of Diminishing Returns
Caffeine is not a perfect substance, however. The sad paradox is that the more you use it, the fewer benefits you receive. Terry Graham, chairman of the Department of Human Health and Nutritional Sciences of the University of Guelph in Canada found that athletes who consumed high levels of caffeine for prolonged periods actually performed worse than athletes who did not use the drug. This is because caffeine is extremely habit-forming; you need more and more to get the same effect over time and the withdrawal is a killer.
Also, caffeine does have its share of negative side effects. The most [1] [2] 下一页 【已有很多网友发表了看法,点击参与讨论】【对英语不懂,点击提问】【英语论坛】【返回首页】
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