Heat cramps are painful, involuntary muscle spasms that usually occur during heavy exercise in hot environments. The spasms may be more intense and more prolonged than are typical nighttime leg cramps. Fluid and electrolyte loss often contribute to heat cramps.

Muscles most often affected include those of your calves, arms, abdominal wall and back, although heat cramps may involve any muscle group involved in exercise.

If you suspect heat cramps

  • Rest briefly and cool down
  • Drink clear juice or an electrolyte-containing sports drink
  • Practice gentle, range-of-motion stretching and gentle massage of the affected muscle group
  • Don't resume strenuous activity for several hours or longer after heat cramps go away
  • Call your doctor if your cramps don't go away within one hour or so

Get the latest health information from Mayo Clinic’s experts.

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

June 26, 2020