时差N小时 路时为什么要甩胳膊?(下)

But although it happens passively, arm swinging plays an important role in making your stride more efficient. It does this by counterbalancing your torso and hips¹ and keeping them from twisting and bobbing too much. Holding your arms still against your sides while walking requires twelve percent more energy than if your arms are allowed to swing naturally. Forcing your arms to swing in sync with the leg on the same side of your body uses a whopping twenty-six percent more energy than normal walking. Even when walkers had their arms strapped² to their sides, so no muscle control was required to keep them still, they used seven percent more energy than when their arms could swing freely. This suggests that arm swinging is not just a passive byproduct of walking, but actually makes walking easier.

尽管挥胳膊是被动发生的，但是挥胳膊在走路中起着很重要的作用。挥胳膊会抵消膝盖和屁股的阀作用，防止它们过度扭曲或挥动。如果走路时你把胳膊放在体侧不动，这比挥动胳膊走路要多消耗百分之十二的能量。如果强迫胳膊和腿向同一方向挥动，会比正常走路多消耗百分之二十六的能量。即使走路时将胳膊绑在体侧，不需要肌肉来保持胳膊不动，也比挥动胳膊是多消耗百分之七的能量。这表明挥动胳膊不是走路的副产品，而是让走路变得更容易。

1 hips   

abbr.high impact polystyrene 高冲击强度聚苯乙烯，耐冲性聚苯乙烯n.臀部( hip的名词复数 )；[建筑学]屋脊；臀围（尺寸）；臀部…的

参考例句：

• She stood with her hands on her hips. 她双手叉腰站着。
• They wiggled their hips to the sound of pop music. 他们随着流行音乐的声音摇晃着臀部。 来自《简明英汉词典》

2 strapped   

adj.用皮带捆住的，用皮带装饰的；身无分文的；缺钱；手头紧v.用皮带捆扎(strap的过去式和过去分词)；用皮带抽打；包扎；给…打绷带

参考例句：

• Make sure that the child is strapped tightly into the buggy. 一定要把孩子牢牢地拴在婴儿车上。 来自《简明英汉词典》
• The soldiers' great coats were strapped on their packs. 战士们的厚大衣扎捆在背包上。 来自《简明英汉词典》