She laid her hand on the hard belly and felt the muscles begin to move.

He went on without purpose for an hour or more, until his muscles began protesting.

I was so cold that my muscles were beginning to ache from it.

And can you see by about now the muscles are beginning to feel.

He could feel the muscles in his stomach begin to tighten.

And that was when, he said, his muscles began to work from memory.

This causes stress, and your back muscles begin to tense.

Her muscles were beginning to ache from the long climb.

Once that threshold is reached, the muscles will begin to form the different movements.

After taking in a long breath, he pushed up until his muscles began to shake.