expend

verb [vt. 及物动词]花费，消耗，耗尽

If you give up exercise, your muscles shrink and fat increases. By the same token, if you expend more energy you will lose fat.
如果你放弃锻炼，肌肉就会萎缩，脂肪会增多。同样地，如果你消耗较多的体能，你就会减掉脂肪。