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What Runners Can Learn From Cheetahs

Back in the 1960s, researchers in Africa clocked the wild cheetah as it ran and determined that at full gallop, a cheetah reached a top speed of about 65 miles per hour, making it easily the world's fastest land mammal. No other quadruped or biped comes close. Galloping quarter horses top out around 47 miles per hour, while sluggish humans, in the person of the world record 100-meter sprinter Usain Bolt, have attained a top speed of less than 28 miles per hour. Even the bullet-trainlike greyhound, similar in build and running style to the cheetah, doesn't surpass 40 miles per hour.

20世紀60年代,非洲的研究人員測量了野生獵豹的奔跑速度,發現獵豹在全速奔跑的時候,速度可以達到每小時65英里左右,輕松奪取陸生哺乳動物的速度桂冠。沒有任何其他四足動物或兩足動物能夠望其項背。疾速奔跑的夸特馬速度可以達到每小時47英里左右,而行動遲緩的人類,即便是創造了世界100米紀錄的短跑運動員尤塞恩·博爾特(Usain Bolt),最快的速度也還不到每小時28英里?;夜窊碛凶訌椓熊囈话愕捏w型,生理構造和奔跑方式都和獵豹相似,就連它的速度也未能超過每小時40英里。

So what is it about the cheetah and its particular physiology or running form that allows it to set such a blazing pace? And can a better understanding of cheetah biomechanics help humans to move faster?


Those were the questions that motivated a group of scientists at the Structure and Motion Laboratory at the University of London, who decided to compare the cheetah with one of its near rivals in speed, the greyhound.

為了回答這些問題,一組來自倫敦大學結構與運動實驗室的(Structure and MotionLaboratory at the University of London)科學家們決定,要對獵豹和與它速度近似的灰狗進行對比實驗。

"The two animals are quite alike in terms of body mass and running form," says Alan H. Wilson, a professor at the Royal Veterinary College at the University of London, who led the study, which was published in The Journal of Experimental Biology.

“這兩種動物在體重和奔跑方式上十分相似,”倫敦大學皇家獸醫學院(Royal Veterinary College at the University of London)的教授艾倫·威爾遜(Alan H. Wilson)說。這個課題由他負責,研究結果發表在《實驗生物學期刊》 (The Journal of Experimental Biology)上。

Both animals employ a running form known as the rotary gallop. Their legs churn in a circular motion, the animal's back bowing and its hind legs reaching almost past its ears at full stride. (Tongues tend to loll, too, but there's no indication that this attribute affects speed.)


"Up to a speed of about 40 miles per hour, there's very little difference," Dr. Wilson says. "But what happens after that," when the cheetah finds another gear and accelerates to 65 miles per hour, "is something we'd like to understand. We believe it can help us to better understand the determinants and limits of speed itself."


But closely studying cheetahs in the wild is logistically challenging, especially if you want exact measurements of running force and stride. So the researchers turned to captive cheetah populations at a zoo in Dunstable, England, and a sanctuary in Pretoria, South Africa. The animals were extensively measured and filmed.


Then some of the English cheetahs were taken to the performance lab and encouraged to chase a chicken-meat lure along a 90-meter track dotted with force plates to chart their strides. Meanwhile, high-speed cameras recorded their every movement from multiple angles.


The researchers repeated the experiment with trained racing greyhounds, then compared the two animals' pace and form.


The first thing they noted was that captive cheetahs are relatively slow, compared with their wild brethren. The galloping zoo-bred cheetahs topped out at a little less than 40 miles per hour, slightly lower than the top speed for the greyhounds.


"That finding was not really unexpected," Dr. Wilson says. Cheetahs that live in zoos do not have to feed themselves. They have less motivation to run hard, even when a chicken lure is waggled enticingly in front of them.


"They also don't necessarily learn to gallop as fast," Dr. Wilson says. "There is almost certainly some amount of speed that depends on learning" to be swift enough to bring down prey.

“它們也不需要學習快速奔跑,” 威爾遜說。“幾乎可以肯定,一部分的速度依賴于學習”,學習的目的則是快到足夠捕殺獵物的程度。

Dr. Wilson is now collecting data on wild cheetahs, but even in the zoo-bred animals, there were hints of their capabilities. When the cheetahs "felt like it," Dr. Wilson says, their leg turnover rate spurted and their pace dramatically increased. They began bringing their legs around faster and faster, their strides lengthening, even as the frequency of their strides increased.


The greyhounds, on the other hand, maintained a fairly even stride frequency throughout their entire run.


The cheetahs also hit the force plates differently from the greyhounds, their paws remaining on the ground slightly longer -- an action that presumably allows the legs to absorb more of the forces generated by the pounding stride.


"One of the limits to speed is that, at some point, you can generate more force than the muscles can withstand," Dr. Wilson says. Striking the ground with such shattering oomph can cause muscles to shred. The cheetahs reduced this risk by letting their paws linger a fraction of a second longer on the ground than the greyhounds did.


The lessons for human runners are somewhat abstract, since we have only two legs and, with rare exceptions, cannot curl them up past our ears, as cheetahs and greyhounds do. "The cheetah's back functions as an extension of its hind legs," Dr. Wilson points out, its spine coiling and extending with each stride, as ours cannot.

這個經驗對于人類跑步者來說有些抽象,因為我們只有兩條腿,而且大多數情況下,我們也不能像獵豹和灰狗那樣,將腿伸展到可以超過耳朵的程度。“獵豹的背部延伸了其后腿的功能。” 威爾遜指出,獵豹的脊柱會隨著每次邁步而一蜷一伸,我們卻不能這樣。

But there are tips we can glean from the cheetah. The speed with which a creature brings its leg back around into position appears to be one of the main determinants of speed, Dr. Wilson says. The faster you reposition the leg, the faster you'll move.


But swift leg turnover requires power. "Compared to the greyhound, the cheetah has bulky upper legs," Dr. Wilson says. Its powerful thigh muscles allow its legs to pump more rapidly than the spindly greyhound's can.


So strengthen your thighs.


And perhaps invest in lightweight racing shoes. "Having less weight in the lower portion of the leg aids in swift repositioning" of the limb, Dr. Wilson says.


Finally, while a dangling lure is optional, being hungry, Dr. Wilson says, at least metaphorically, "probably helps quite a bit."


Gretchen Reynolds is the author of "The First 20 Minutes: Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer" (Hudson Street Press, 2012).

格雷琴·雷諾茲(GretchenReynolds)是《前20分鐘:神奇科學告訴你如何更好地運動、鍛煉和生活》(The First 20 Minutes:Surprising Science Reveals How We Can Exercise Better, Train Smarter, LiveLonger)的作者。(哈德森街出版社,2012年)

We hope you'll "Like" the new Well on Facebook, where you'll find news and conversations about fitness, food and family health. And you can track your own running progress with the Run Well training tool.

我們希望您會“喜歡”臉譜(Facebook)上的“新源”(new well),上面有關于健康、食物和家庭健康的信息和對話。您還能利用“跑得好”訓練工具(the Run Well training tool)來跟蹤自己的跑步進度。
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