Collocations for muscle - noun

hard, powerful, strong | taut, tense, tight | cramped
I walked up and down the aisle to stretch my cramped muscles.

tired | abdominal, arm, calf, facial, heart, thigh, etc. | skeletal

flex, tense
He flexed his muscles, then set off to run.

relax
Learn how to relax tense muscles.

stretch | build (up), strengthen, tone (up) | pull, tear
I laughed so hard I almost pulled a muscle.

ache | clench, contract, stiffen, tense, tighten | go limp, loosen, relax, slacken | quiver, ripple, twitch
His muscles rippled beneath his T-shirt as he worked.

control sth
the muscles controlling speech production

cell, fibre, tissue | group | disease, pain | contraction, relaxation, spasm, tension | tone

~ in
The muscles in my face tensed.