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人类为什么能成为地球上最凶猛的短跑健将

工夫:2018-04-25 12:08 阅读:

Each year, a small town in Wales holds the Man Versus Horse Marathon. It's a 22-mile race between riders on horseback and runners. And, while horses often win, humans will sometimes prevail. 威尔士的一个小镇每年都市举行“人马短跑大赛”,由骑马者和跑步者配合到场,赛程约为35公里。固然骑马者经常胜出,但人类偶然也能得胜。 So what makes humans such endurance running superstars? 那么,人类为什么能成为短跑健将呢? The secret weapon is our sweat. We have 2-4 million sweat glands all over our body, which means we can run and cool ourselves at the same time. Having no fur is also a huge plus. 我们的机密武器是汗液。人类满身掩盖着200万至400万个汗腺——也便是说,我们可以一边跑步一边降温。别的,没有皮毛也是一大劣势。 In contrast, dogs rely on panting to cool down, and other animals, like horses and camels, also sweat, but less effectively. As a result, they overheat faster and must slow down sooner. 相较而言,狗要靠喘息降温;马、骆驼等其他植物固然也流汗,但降温结果不如人类。因而,它们的体温会更快过热,需求尽早加速。 The mechanics of our running stride also makes us particularly well-suited for endurance running. A human's running gait has two main phases: Aerial when both feet are off the ground and Stance when at least one foot touches the ground. 别的,人类的跑步步法也使我们分外合适短跑。人类跑步的步态有两步——腾空:双脚均离地;站立:至多一只脚着地。 While in the air, gravity pulls us down, which generates a lot of kinetic energy. However, the second we hit the ground, we instantly decelerate, losing that kinetic energy in the process. 腾空时,重力会把我们往下拉,这个进程发生了少量动能。不外,着地时会立即加速,得到这种动能。 Here's where our special adaptations come in. The tendons and muscles in our legs are very springy. They act like a pogo stick, converting kinetic energy from the aerial phase into elastic potential energy, which we can use later. 而人类共同的顺应性就表现在这里。我们的大腿肌腱和肌肉极具弹力,它们可以像弹跳器一样将动能转化为弹性势能,以供之后应用。 In fact, our IT band can store 15-20 times more elastic energy than a chimpanzee's similar body part, the fascia lata. When it comes time to step off, those springy tendons can turn 50% of that elastic pogo-stick energy back into kinetic, making it easier to propel forward. Without that extra energy, we'd have to exert that much more effort just to take a step. 现实上,人类的髂胫束(包绕大腿的深筋膜)可以贮存的弹性势能是黑猩猩的类似部位阔筋膜的15-20倍。当我们迈步时,富有弹性的筋腱可以将50%的弹性势能转化为动能,使我们更容易行进。假如没有这种额定能量,那么我们需求支付更多高兴,才干够行进一步。

So, why did humans get to be such great endurance runners, anyway? 那么,人类为何能成为云云杰出的短跑健将呢? Some anthropologists believe this became important around 2-3 million years ago, when we started hunting and scavenging. Because we couldn't chase down a gazelle like a cheetah, early humans learned persistence hunting. Where they would track prey over long distances until the prey either overheated or was driven into a trap. 一些人类学家以为,约莫在两三百万年前,当人类开端打猎和寻食时,短跑才能变得至关紧张。由于人类无法像猎豹一样追捕瞪羚羊,于是我们学会了耐力打猎。他们会追踪猎物很长一段间隔,直到它们体温过热或被逼进圈套。 In fact, persistence hunting remained in use until 2014, such as with the San people of the Kalahari Desert. 现实上,到了21世纪,仍然有人类在运用这种打猎办法,比方,喀拉哈里戈壁的非洲原住民桑人。 But distance running can still help you, even if you're not interested in running down your next meal. 即使你如今对追猎寻食没兴味,但短跑仍然无益身材。 Studies show running can lower body weight, body fat, and cholesterol levels. And the longer you train, the greater the health benefits. Just one year of training has been shown to reduce body weight by about 7 lbs, lower body fat by 2.7% and decrease resting heart rate by 2.7%. 研讨表现,跑步可以低落体重、体脂和胆固醇程度。跑步工夫越久,安康好处越分明。一年的短跑训练可以使体重低落约3公斤,体脂低落2.7%,静息心率低落2.7%。