为什么跑步能跑出好心情

lao2lao2

Yes, Running Can Make You High

By GINA KOLATA
Published: March 27, 2008



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.

http://www.nytimes.com/2008/03/2 ... fitnessandnutrition


跑步跑出好心情，一定有很多人都听过这种说法，而且对此深信不疑，特别是运动员，可能大部分都经历过这种感觉。但由于这种说法从未得到科学的试验证实，因此科学家们一直对此持保留态度。然而，最近德国研究人员应用神经科学的先进技术证实了这种民间信仰的真实性：跑步可以使与情绪有关的大脑内啡肽大量产生，且体内内啡肽产生量越多，这种情绪调节作用就越明显。研究结果发表在最新一期的《大脑皮层》杂志上。

有人说，他们跑步时感觉非常好，就像吃了情绪改善剂。但这种感觉到底是真实的，还是一种错觉？如果它是真实的，那么究竟应该是什么感觉？又是什么原因引起的呢？ 经历过这种感觉的人都说这种感觉不同寻常。他们在运动后可能会感到轻松或平静，但偶尔又会感到欣快。那么，冷静本身是否就代表一个运动员的最佳状态呢？

很多时候，那些经历过强烈欣快感的人说，在进行耐力运动后这种感觉就会出现。我的朋友Marian Westley 说，她跑完马拉松后会有这种感觉，而且情绪不稳定，一看见小狗就落泪。还有些人在短时间高强度运动（例如跑5公里比赛）中感觉自己近乎崩溃时，这种舒畅的感觉就会出现。但也有一些人和我朋友Annie Hiniker相像，当她结束了5公里比赛后，唯一的感觉就是欣快。

跑出好心情假说认为，运动能使大脑发生生化效应。化学物质的释放会改变运动员的情绪，这些化学物质就是大脑内自然存在的阿片类物质内啡肽。跑步不是唯一获得这种感觉的方式，在很多激烈运动或耐力运动时也会产生。该假说的问题是，研究者不可能在某人运动之前和之后进行腰椎穿刺来检查大脑内啡肽的含量。研究人员可以检测人们跑步后的血中内啡肽水平，但是血液中内啡肽仅代表人体应激反应所产生的内啡肽，不能由血液输送到大脑，对改善情绪没有作用。所以30年多年来，跑出好心情仍然是一个未经证实的假说。

但现在的医学技术的迅猛发展已经可以让人们解释以前无法证实的假说。这项新研究的领导者波昂大学Henning Boecker博士说，当他意识到研究人员用于疼痛研究的方法能够直接应用时，冒出了检测内啡肽假说的想法。这个想法就是用PET扫描结合现有最新的化学试剂显示大脑中的内啡肽，比较运动员在长跑前后大脑发生的变化。如果扫描结果显示，内啡肽正在产生且聚集在与情绪有关的大脑区域，那就是内啡肽假说的直接证据。如果那些不了解研究目的运动员也显示出运动强度与内啡肽产量相关的情绪变化，那将是这一论点的另一个有力证据。

Boecker博士boecker和他的同事招募了10名长跑选手，并告诉他们研究目的是大脑中的阿片受体，但运动员并不知道调查人员正在研究内啡肽释放与运动员情绪的关系。运动员在跑步前后两小时分别进行一次PET扫描。另外，跑步前后还要分别接受一次情绪方面的标准心理测试。数据显示，内啡肽在奔跑过程中产生，并逐渐向大脑调节情绪的区域聚集，特别是边缘系统和额前区。

Boecker博士解释说，当人们陷入爱河或者听到令人陶醉的音乐，例如拉赫曼尼诺夫第三钢琴协奏曲时，边缘系统和额前区表现活跃。运动员的欣快感越明显，说明大脑内啡肽的产生越多。Boecker在业余时间也会做些跑步和脚踏车等运动，他说他在跑步之后会感到完全放松，而且头脑非常清醒。这与研究对象所发生的情况相同，他说：“你真的可以发现两小时运动后的差异。你从他们的脸上就可以观察到这种变化。”

可以说，Boecker的研究开创了运动科学的新篇章。内啡肽研究领域内未参与该研究的主要研究者们均对这项研究结果表示认可。约翰霍普金斯大学神经科学教授Solomon Snyder是上世纪70年代内啡肽的发现者，他说，“这项研究意义深远。” 密西根大学神经科学教授Huda Akil也认为，这项研究取得了该领域内的首次进展。

在另一项随访研究中，Boecker博士正在研究跑步是否会影响痛觉。“已有研究表明，运动员对痛觉的耐受程度较高，”他说。“你必须给予较强的疼痛刺激，他们才会说，‘好了，伤到我了。’”他还讲了很多关于运动员发生应力性骨折，甚至心脏病发作后仍坚持跑步的故事。

Boecker博士和他的同事招募了20名马拉松运动员和同样数量的非马拉松运动员，研究他们跑步后的痛觉，以及脑部扫描是否有变化。他还让受试者步行以观察这种效应是否由运动强度所致。非运动员的受试者可以帮助研究人员评估是否未受过训练的人会经历同样的感受。

研究人员认为，有些人喜欢激烈运动的一个可能原因就是运动后情绪和痛觉的这种变化。Annie喜欢跑步，但一直不知道究竟为什么。她的丈夫告诉她说，她的脸在跑步时总是充满了喜悦。也许她也得到了运动员的好心情。现在，跑步者的好心情已经能够被定义和测量，而且还能估算出它的结果，甚至能为那些不喜欢运动但又必须运动的人带来希望。他们可以通过学习一些技巧，来获取那种对运动上瘾的感觉。