physical effort

A healthy boy can put forth an amazing amount of physical effort and be fresh at the end of a day of play.

She forced herself to speak calmly; though her hands were clenched in sheer physical effort to quell the riot in heart and brain.

Even as a girl she had been at her best in vigorous effort, he remembered; physical effort, when there was no other kind at hand.

In this wonderful old world no new land has been discovered without physical effort.

Luckily for poor human nature, mental stress and physical effort rarely unite forces.