Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.

The flow of water within a muscle fiber may dictate how quickly muscle can contract, according to a new study. The flow of water within a muscle fiber may dictate how quickly muscle can contract, ...

In a serendipitous discovery, UC San Diego researchers using cryo-EM technology captured the first visualizations of the 3-D structure of the muscle acetylcholine receptor in fetal and adult muscles.

Medically reviewed by Katrina Carter, DPT Key Takeaways Voluntary muscles can be controlled by the person, like muscles in your neck and legs. Involuntary muscles work without you thinking about it, ...

Isometric exercises are exercises that involve the contraction of muscles without any movement in the surrounding joints. Most muscle strengthening exercises involve moving the joints, using the ...

Washington, D.C.—New global imaging and topographic data from MESSENGER* show that the innermost planet has contracted far more than previous estimates. The results are based on a global study of more ...

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? Two opposite types of faults, normal and reverse, help explain our undersea mountain ...