在山里慢跑是一种非常耗费体力的锻炼方式。

Jogging in the mountains is a ___strenuous form of exercise.

在竞技体育中，追求完美需要付出艰苦卓绝的努力。

In competitive sports, the pursuit of perfection requires ___strenuous effort.

这位运动员艰苦的训练计划让他筋疲力尽。

The athlete's ___strenuous training program left him exhausted.