Adrenaline increases the "alertness" of the nervous system, meaning it's ready to trigger muscle contraction. It also increases the amount of blood flow and changes the tension of the muscles, which, ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...

Doctors identify these movements as 'fasciculations', because they occur when individual nerve fibers, which control small muscle groups activate independently to produce brief muscle contractions.

We've all been there before. Running along the basketball court or swimming across the pool, when, all of a sudden, we experience a sharp pain in our foot or leg. Muscle cramps are common, affect ...

While sitting still at your desk or watching TV, you sense a feeling of muscular discomfort in your arm or leg. It’s not quite a charley horse, but you can see your skin pulsating involuntarily, as if ...

If you’ve ever wondered why some people seem to adapt more quickly to resistance training, it’s probably due to the type of skeletal muscle tissue they have. Each of our muscle fibers is either ...

Microscopic tears of the muscle away from the lining of the bone causes the pain. Predisposing factors include overpronation ...

The lower leg lies between the knee and ankle and works with the upper leg and foot to help perform key functions. In the leg are a number of bones, muscles, tendons, nerves and blood vessels. These ...