為什么我們走路時雙臂伸直，而跑步時雙臂彎曲?

為什么我們走路時雙臂伸直，而跑步時雙臂彎曲?

Running with your arms bent and walking with your arms straight is what most of us do, but until recently, scientists didn't know why.

大多數(shù)人都是彎著胳膊跑步，伸直胳膊走路，但直到最近，科學(xué)家們才知道為什么。

To find out, Andrew Yegian and his fellow researchers at Harvard University had eight volunteers walk and run on a treadmill with their arms straight and bent. Six of the participants wore oxygen masks to record how much oxygen they used. Researchers tracked all the volunteers' movements using reflective markers on their shoulders, wrists and elbows, according to The Guardian.

為了找到答案，安德魯·耶吉安和他在哈佛大學(xué)的同事讓8名志愿者在跑步機上行走和跑步，他們的手臂伸直或彎曲。六名參與者戴著氧氣面罩，記錄他們使用了多少氧氣。據(jù)《衛(wèi)報》報道，研究人員用志愿者肩膀、手腕和肘部的反光標(biāo)記跟蹤了所有志愿者的運動。

The team predicted that it was more efficient to have straight arms while walking and bent arms while running, but they were only half right.

研究小組預(yù)測，走路時伸直胳膊和跑步時彎曲胳膊效率更高，但他們只對了一半。

They found that walking with arms bent used more energy than walking with straight arms, increasing oxygen consumption by 11%. But surprisingly, running with bent arms was no more efficient than running with straight arms.

他們發(fā)現(xiàn)彎曲手臂走路比伸直手臂走路消耗更多的能量，增加了11%的耗氧量。但令人驚訝的是，彎曲手臂跑步并不比伸直手臂跑步更有效。

"Pretty much every subject in the study said that straight-arm running was the most challenging condition," Yegian told New Scientist. "That’s why it was very surprising when we couldn’t find any difference in the energetics.”

耶吉安在接受《新科學(xué)家》雜志采訪時說:“幾乎所有參與研究的人都說，伸直手臂跑步是最具挑戰(zhàn)性的。”“這就是為什么當(dāng)我們在能量學(xué)上找不到任何不同時，會感到非常驚訝。”

We tend to walk with our arms straight and run with our arms bent. (Photo: maxpro/Shutterstock)

The study, which was published in the Journal of Experimental Biology, involved students who ranged from marathon runners to those who ran just a few times a week.

這項研究發(fā)表在《實驗生物學(xué)雜志》上，研究對象包括從馬拉松運動員到每周只跑幾次的學(xué)生。

The researchers say they don't know why we usually bend our arms when we run. Yegian says he thinks there has to be some beneficial reason. It could be because bending the arms helps stabilize the head.

研究人員表示，他們不知道為什么我們跑步時通常會彎曲手臂。耶吉安說，他認(rèn)為肯定有一些有益的原因。這可能是因為彎曲手臂有助于穩(wěn)定頭部。

And because the research was only conducted at low running speeds, the benefit of arm bending may be more obvious at higher speeds.

由于這項研究只在低速下進(jìn)行，所以在高速下彎曲手臂的好處可能更明顯。

Yegian plans to do more testing to find out.

耶吉安計劃做更多的測試來找出答案。

He told The Guardian, "We have a pretty good idea now that energy is why we keep our arms straight when we’re walking and there’s probably a specific reason for bending your arms during running."

他在接受《衛(wèi)報》采訪時表示:“我們現(xiàn)在有了一個很好的想法，那就是能量是我們走路時保持手臂伸直的原因，跑步時彎曲手臂可能有一個特定的原因。”