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.

Muscle contractions during your menstrual cycle and pregnancy serve distinct purposes. Period cramps take place as the uterus ...

Human movement occurs through contraction of the basic unit of the muscle cell, the sarcomere. Sarcomeres have long been considered to be arranged end-to-end in series along the length of the muscle ...

For most people, swallowing is second nature, but how does it occur, and why do some people have difficulty with it? Researchers at Kyushu University in Japan have started to tackle these questions by ...

What Are Eccentric and Concentric Contractions? Eccentric contractions occur when a muscle lengthens under load, such as lowering a dumbbell during a biceps curl. Concentric contractions happen when ...

Sustained muscle contraction occurs through interactions between actin and myosin filaments within sarcomeres and requires a constant supply of adenosine triphosphate (ATP) from nearby mitochondria.

At one point or another, we’ve all experienced the unexpected, intense pain of a muscle cramp. Muscle cramps, also known as muscle spasms or charley horses, are the involuntary contraction of muscle ...