为什么黑人擅长短跑而白人是游泳比赛的常胜将军？科学家给出了新解释，这是由肚脐的位置决定的。

　　The researchers found that the position of the navel in relation to the rest of their body affects athletic ability. This is because the naval is the body's centre of gravity. A higher naval meaning a higher centre of gravity, so your body is pulled forward faster. While a lower navel means a longer torso which makes for a better swimmer.

　　研究人员发现肚脐在人体的相对位置能够影响到人的运动能力。因为它是人体的重心所在。肚脐位置高，重心就高，因此向前冲的速度快。反之，肚脐位置低，躯干长，游泳就快。

　　The researchers say their findings prove why black people are more likely to sprint faster while white people make swifter swimmers. A professor from Duke University explains, "What matters is not total height but the position of the belly-button, or centre of gravity."

　　研究人员称他们的发现找到了黑人善跑而白人善游的原因。美国杜克大学一位教授解释说：“起决定作用的不是身高而是肚脐的位置，也就是人体的重心位置。”

　　It so happens that in the architecture of the human body of West African-origin runners, the centre of gravity is significantly higher than in runners of European origin which puts them at an advantage in sprints on the track.

　　通常，西非运动员的重心明显比欧洲运动员的要高很多。这就使他们在短跑项目上占据优势。

　　Individuals of West African-origin have longer legs than European-origin athletes, which means their belly-buttons are three centimeters (1.18 inches) higher than whites. That means the black athletes have a "hidden height" that which gives them a significant speed advantage on the track.

　　从个体比较，西非运动员比欧洲运动员的腿长，他们肚脐的位置平均比白人高出三厘米。这个隐藏高度使他们在跑道上速度占优。

　　In the pool, meanwhile, whites have the advantage because they have longer torsos, so their belly-buttons sit lower on the body.

　　相比之下，在游泳项目上，白人较长的躯干和位置较低的肚脐是有利条件。

　　"Swimming is the art of surfing the wave created by the swimmer,"said the professor. "The swimmer who makes the bigger wave is the faster swimmer, and a longer torso makes a bigger wave. Europeans have a three-percent longer torso than West Africans, which gives them a 1.5-percent speed advantage in the pool," he said.

　　该教授说：“游泳是冲浪艺术。游泳者制造浪花。浪花造的越大，游得就越快。游泳者的躯干越长，就越容易制造大朵浪花。欧洲人的躯干一般比西非人长3%，这就使得他们游泳时有1.5%的速度优势。”