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.

Flexing your muscles is more than just a way to show off the results of your strength training workouts. It can also be a way to build strength. Muscle flexing is more accurately known as muscle ...

Tight and rigid muscles are often the result of injury. Sometimes, muscle tightness and rigidity can occur with other symptoms, such as muscle pain and spasms, or reduced mobility. Mild muscle ...