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》

The exercises are designed to stretch and tone your leg muscles.

这些活动目的在于伸展和增强你的腿部肌肉。

《牛津词典》

Soreness occurs since your leg muscles aren't used to that movement.

因为你的腿部肌肉不习惯这种运动，所以会感到酸痛。

youdao

They jump on an electronic plate to measure whether their leg muscles are more catlike or powerful.

WSJ: U.S. Ski Team Pins Hopes for Sochi on Science

Decreased oxygenation of leg muscles due to peripheral vascular disease and the pain of diabetic neuropathy can also be mistaken for cramps.

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Their spinal cords, in other words, had learnt to recognise nerve signals coming from their leg muscles and to generate appropriate outgoing signals to keep the movement going.

ECONOMIST: Neurology