When you ride a bike, you exercise all of the leg muscles.

骑自行车时，你可以锻炼腿部的全部肌肉。

《柯林斯英汉双解大词典》

This exercise leg lines.

这样可以锻炼小腿线条。

youdao

The exercise consists of stretching and contracting the leg muscles.

此项训练包括伸展和收缩腿部肌肉。

《牛津词典》

The two main exercises for quadriceps include leg extensions (usually done on an exercise machine) and squats.

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Ms. Crowe receives regular home visits from occupational and physical therapists, who work with her on puzzles, problem-solving games and exercise, including walking, stretching, leg exercises and light weights.

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