What is a Charley horse? If you have ever had an incredibly painful leg cramp come on fast and furiously you have likely experienced a Charley horse. This type of muscle spasm tends to occur when ...

Learn more about the causes, risk factors, diagnosis, treatment, & prevention of Charley horses - cramps caused by muscle spasms, involuntary contractions of one or more muscles ...

During a charley horse, an involuntary signal is sent to the muscle without the “proper instructions,” she says, and as a result, the muscle fibers shorten and contract too hard.

This is sometimes called a “charley horse” – another term for a leg cramp, spasm or contraction that happens while you’re sleeping. These are just one type of leg cramp.

Before engaging in physical activity, ensure you warm up properly and avoid overexertion. Interestingly, the terms 'Charley Horse' and 'leg cramps' are often used interchangeably.