1、After years of inactivity, his arms and legs became muscleless and weak.

多年来不运动后，他的胳膊和腿变得没有肌肉且虚弱。

2、The muscleless bodybuilder struggled to lift even the lightest weights.

缺乏肌肉的健美运动员试图举起甚至最轻的重量都很困难。