Heat cramps usually affect workers who sweat a lot during strenuous activity. This sweating depletes the body's salt and moisture levels.

Low salt levels in muscles causes painful cramps. Heat cramps may also be a symptom of heat exhaustion.

• Muscle cramps, pain, or spasms in the abdomen, arms, or legs

First Aid
Workers with heat cramps should:
• Drink water and have a snack and/or carbohydrate-electrolyte replacement liquid (e.g., sports drinks) every 15 to 20 minutes.
• Avoid salt tablets.
• Get medical help if the worker has heart problems, is on a low sodium diet, or if cramps do not subside within 1 hour.

From: cdc,gov
Publishing date: 25/2/2017