它用到的一些肌肉，是你们中大部分人平时没怎么用到的。

Some of the muscles it uses are not usually used by most of you.

youdao

当我们的身体一遍又一遍地做同样的动作时，会过度使用一些肌肉，从而导致劳损和受伤。

When we do the same movements with our bodies over and over again, we overuse some muscles and that overuse can lead to strain and injury.

youdao

随着年纪的增大，我们会失去一些肌肉组织。

As we age we lose muscle tissue.

《柯林斯英汉双解大词典》

It's exercising a set of muscles that a lot of you have not spent a lot of time exercising.

它用到的一些肌肉,是你们中大部分人平时没怎么用到的。

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