VIP标识 上网做生意,首选VIP会员| 设为首页| 加入桌面| | 手机版| 无图版| RSS订阅
食品伙伴网,关注食品安全,探讨食品技术
 
当前位置: 首页 » 专业英语 » 英语短文 » 正文

跑步能使你兴奋

放大字体  缩小字体 发布日期:2008-08-23  浏览次数:1834
核心提示:THE runners high: Every athlete has heard of it, most seem to believe in it and many say they have experienced it. But for years scientists have reserved judgment because no rigorous test confirmed its existence. Yes, some people reported that they


THE runner’s high: Every athlete has heard of it, most seem to believe in it and many say they have experienced it. But for years scientists have reserved judgment because no rigorous test confirmed its existence.

Yes, some people reported that they felt so good when they exercised that it was as if they had taken mood-altering drugs. But was that feeling real or just a delusion? And even if it was real, what was the feeling supposed to be, and what caused it?

Some who said they had experienced a runner’s high said it was uncommon. They might feel relaxed or at peace after exercising, but only occasionally did they feel euphoric. Was the calmness itself a runner’s high?

Often, those who said they experienced an intense euphoria reported that it came after an endurance event.

My friend Marian Westley said her runner’s high came at the end of a marathon, and it was paired with such volatile emotions that the sight of a puppy had the power to make her weep.

Others said they experienced a high when pushing themselves almost to the point of collapse in a short, intense effort, such as running a five-kilometer race.

But then there are those like my friend Annie Hiniker, who says that when she finishes a 5-k race, the last thing she feels is euphoric. “I feel like I want to throw up,” she said.

The runner’s-high hypothesis proposed that there were real biochemical effects of exercise on the brain. Chemicals were released that could change an athlete’s mood, and those chemicals were endorphins, the brain’s naturally occurring opiates. Running was not the only way to get the feeling; it could also occur with most intense or endurance exercise.

The problem with the hypothesis was that it was not feasible to do a spinal tap before and after someone exercised to look for a flood of endorphins in the brain. Researchers could detect endorphins in people’s blood after a run, but those endorphins were part of the body’s stress response and could not travel from the blood to the brain. They were not responsible for elevating one’s mood. So for more than 30 years, the runner’s high remained an unproved hypothesis.

But now medical technology has caught up with exercise lore. Researchers in Germany, using advances in neuroscience, report in the current issue of the journal Cerebral Cortex that the folk belief is true: Running does elicit a flood of endorphins in the brain. The endorphins are associated with mood changes, and the more endorphins a runner’s body pumps out, the greater the effect.

Leading endorphin researchers not associated with the study said they accepted its findings.

“Impressive,” said Dr. Solomon Snyder, a neuroscience professor at Johns Hopkins and a discoverer of endorphins in the 1970’s.

“I like it,” said Huda Akil, a professor of neurosciences at the University of Michigan. “This is the first time someone took this head on. It wasn’t that the idea was not the right idea. It was that the evidence was not there.”

For athletes, the study offers a sort of vindication that runner’s high is not just a New Agey excuse for their claims of feeling good after a hard workout.

For athletes and nonathletes alike, the results are opening a new chapter in exercise science. They show that it is possible to define and measure the runner’s high and that it should be possible to figure out what brings it on. They even offer hope for those who do not enjoy exercise but do it anyway. These exercisers might learn techniques to elicit a feeling that makes working out positively addictive.

The lead researcher for the new study, Dr. Henning Boecker of the University of Bonn, said he got the idea of testing the endorphin hypothesis when he realized that methods he and others were using to study pain were directly applicable.

The idea was to use PET scans combined with recently available chemicals that reveal endorphins in the brain, to compare runners’ brains before and after a long run. If the scans showed that endorphins were being produced and were attaching themselves to areas of the brain involved with mood, that would be direct evidence for the endorphin hypothesis. And if the runners, who were not told what the study was looking for, also reported mood changes whose intensity correlated with the amount of endorphins produced, that would be another clincher for the argument.

Dr. Boecker and colleagues recruited 10 distance runners and told them they were studying opioid receptors in the brain. But the runners did not realize that the investigators were studying the release of endorphins and the runner’s high. The athletes had a PET scan before and after a two-hour run. They also took a standard psychological test that indicated their mood before and after running.

The data showed that, indeed, endorphins were produced during running and were attaching themselves to areas of the brain associated with emotions, in particular the limbic and prefrontal areas.

The limbic and prefrontal areas, Dr. Boecker said, are activated when people are involved in romantic love affairs or, he said, “when you hear music that gives you a chill of euphoria, like Rachmaninoff’s Piano Concerto No. 3.” The greater the euphoria the runners reported, the more endorphins in their brain.

“Some people have these really extreme experiences with very long or intensive training,” said Dr. Boecker, a casual runner and cyclist, who said he feels completely relaxed and his head is clearer after a run.

That was also what happened to the study subjects, he said: “You could really see the difference after two hours of running. You could see it in their faces.”

In a follow-up study, Dr. Boecker is investigating if running affects pain perception. “There are studies that showed enhanced pain tolerance in runners,” he said. “You have to give higher pain stimuli before they say, ‘O.K., this hurts.’ ”

And, he said, there are stories of runners who had stress fractures, even heart attacks, and kept on running.

Dr. Boecker and his colleagues have recruited 20 marathon runners and a similar number of nonathletes and are studying the perception of pain after a run, and whether there are related changes in brain scans. He is also having the subjects walk to see whether the effects, if any, are because of the intensity of the exercise.

The nonathletes can help investigators assess whether untrained people experience the same effects. Maybe one reason some people love intense exercise and others do not is that some respond with a runner’s high or changed pain perception.

Annie might question that. She loves to run, but wonders why. But her husband tells her that the look on her face when she is running is just blissful. So maybe even she gets a runner’s high.

跑步的人很兴奋,每位运动员都听到过这种说法,多数人看来相信这种说法,许多人说他们有过类似的经历。但是多年以来科学家们保留对此的态度,因为没有严格的实验证明它的存在。

没错,一些人说他们在运动时感觉那么好,仿佛是服用了改变情绪的药物一般。但是这究竟是一种真实的感觉还只是一种幻觉?即使这种感觉是真实的,它应该是种什么感觉,又是什么引起的这种感觉呢?

一些表示经历过跑步者兴奋的人说,这种感觉是不寻常的。锻炼后人可能觉得放松或平静,而只在偶然的情况下,他们才会感觉精神陶醉。难道平静本身就是跑步者的兴奋吗?

那些说过自己经历过强烈陶醉感的人经常说,这种感觉出现在长时间的活动后。

我的朋友玛丽安·威斯利说,她那次跑步者的兴奋是在一次马拉松后。那种感觉下她是如此多愁善感,看见一只小狗,也能让她感伤落泪。

其他人说,当他们在短时间内剧烈地运动,比如跑5公里赛跑,累得自己几乎崩溃时,经历了兴奋。

可是还有其他人一些人,像我的朋友安妮·海内克,她说,跑完5公里后,她最不可能有的感觉就是陶醉。她说,”我感觉都要吐了。“

这种跑步者兴奋假说提出,锻炼有真实存在的对大脑的生化影响。人体释放出能够改变运动员情绪的化学物质,这些化学物质就是内啡肽--大脑的天然鸦片。跑步不是获得这种感觉的唯一方法,多数紧张或持续的运动都能产生这种感觉。

这种假说的问题是,要在人运动前和运动后都抽取精髓液来寻找大脑中内啡肽大量增加的证据是不可行的。研究人员能够检测到人在跑步后血液中的内啡肽,但是那些内啡肽是人体紧张反应的一部分,不能从血液中运输到大脑,他们不是提高人情绪的原因。所以30多年来,跑步者兴奋一直作为一项未经证明的假说。

但是现在医学技术已经赶上了运动学说。最新一期的大脑皮质期刊上报道说,德国的研究人员使用神经科学的尖端技术,证明民间的说法是正确的:跑步确实导致大脑中释放大量的内啡肽。这种内啡肽与情绪变化有联系,跑步者身体中产生的内啡肽越多,效果越明显。

这项新研究的首席研究员,波恩大学的海宁·勃克博士说,当他意识到可以直接使用他和同事们用来研究痛感的方法时,他想出了检测内啡肽假说的方法。

这种方法是使用PET(正电子发射断层扫描)扫描与最近出现的可以显示大脑中内啡肽的化学物质结合,来比较跑步者在长跑前后的大脑。如果扫描显示内啡肽产生并依附在大脑中与情绪有关的区域,这将是内啡肽假说的直接证据。而且,如果发现跑步者,他们事先不知道研究的目的,也出现与产生的内啡肽的量相关的情绪变化,那将是这种假说的另一个决定性证据。

勃克博士及其同事们招募了10名长跑选手,告诉他们说正在进行大脑中鸦片感受器的研究,但是这些长跑选手不知道研究人员正左研究内啡肽的释放和跑步者兴奋的关系。运动员们先做了一次PET扫描,在2个小时的跑步后又进行了一次扫描。他们还接受了一次标准的心理测试,以标明他们在跑步前后的情绪变化。

数据表明,确实在跑步中产生了内啡肽,并且依附在大脑与感情有关的区域,尤其是在边缘和额叶前部。

勃克博士说,当人们发生浪漫的爱情时大脑的边缘和额叶前部就活跃;或者是,他说,“当你听到一首让你陶醉得战栗的乐曲时,比如,拉赫马尼诺夫的第三钢琴协奏曲。”运动员所感到的陶醉感越强,他们大脑中的内啡肽就越多。

勃克博士说“一些人在经过很长时间或强烈的训练后,获得这样的极端经历“。他本身就是一位自行车爱好者,偶尔跑跑步。他说,他在跑步过后觉得彻底放松、头脑清醒。

研究项目也是这样的,他说,“你真该看看两个小时的跑步造成的不同,你能从他们脸上看出来。”

在一项后续研究中,勃克博士正在调查跑步是否影响痛感。他说,“有些研究表明跑步者的疼痛耐受力增强了,你必须给予他们更大的痛刺激,他们才会说‘对了,这很疼’。“

而且,他说,有些跑步者的故事说他们遇到了应力性骨折、甚至是心脏病,却还继续跑。

勃克博士及其同事们已经招募了20名跑马拉松选手和同等数目的不跑马拉松的人,正在研究跑步后的痛感差异,和大脑是否有相关的扫描变化。他还让研究对象进行走路,看看那些影响是否同运动的强度有关系,有多少关系。

那些非运动员能够帮助研究人员评估未经训练的的人们是否经受同样的影响。也许有些人喜欢强烈训练而另一些人不喜欢的原因是有些人对跑步者的兴奋或痛感变化有响应而另一些人没有。

安妮也许怀疑这一点。她喜欢跑步,却不知道为什么。她丈夫告诉她,当她跑步时她脸上的表情幸福无比。或许,她也得到了跑步者的兴奋

更多翻译详细信息请点击:http://www.trans1.cn
 
关键词: 跑步 兴奋
[ 网刊订阅 ]  [ 专业英语搜索 ]  [ ]  [ 告诉好友 ]  [ 打印本文 ]  [ 关闭窗口 ] [ 返回顶部 ]

 
0条 [查看全部]  相关评论

 
推荐图文
推荐专业英语
点击排行