A back spasm involves a sudden, involuntary muscle contraction that can be set off by something as routine as lifting a bag or sitting for too long. Muscle fatigue, dehydration, and nerve irritation ...

Add Yahoo as a preferred source to see more of our stories on Google. Many of us have felt a muscle in some part of our body suddenly and involuntarily tighten, causing a twitch or even severe cramp.

A muscle spasm — also known as a charley horse, muscle cramp or twitch — is a sudden, involuntary movement in one or more muscles. Common causes include stress, exercise, or dehydration, but nerve ...

Add Yahoo as a preferred source to see more of our stories on Google. Unfortunately, pain and injury can be a few downsides of an active lifestyle. A combination of genetics and incomplete cool-downs ...