In general, warm up by focusing first on large muscle groups, such as your hamstrings.

通常，热身首先注重在在大的肌肉群，例如你的大腿。

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Swimming is great exercise because it USES both large muscle groups (arms and legs).

游泳是极好的运动，因为游泳同时运用到了胳膊和腿的大肌肉群。

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The movement of large muscle groups will help to stimulate bone growth and strengthening.

而大肌肉群的运动有助于刺激骨骼的生长和强化。

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Aerobic activity is a repetitive rhythmic exercise involving large muscle groups such as legs, shoulders and arms.

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