纳山：肌肉疲劳的其中一个原因是肌肉不够强壮有力，还有就是运动过度。

Nathan: And one of the reasons they get tired is because they're not strong and you overdo the activity.

youdao

纳山：肌肉疲劳的其中一个原因是肌肉不够强壮有力，还有就是运动过度。

Nathan: And one of the reasons they get tired is because they're not strong and you overdo the activity.

youdao