What should you know about dehydration and rhabdomyolysis?

Rhabdomyolysis can follow unusually intense exercise, crush injury, heat exposure, prolonged immobility, or another source of muscle damage. Dehydration reduces available fluid and may make it harder for the kidneys to handle substances released by injured muscle. Muscle pain, marked weakness, swelling, and unusually dark urine are concerning features. Ordinary muscle soreness after exercise generally improves with rest, but severe or unusual symptoms deserve a clinical assessment rather than self-diagnosis.

Stop strenuous exercise and move to a cool place. If you are alert and able to drink, take fluids in small, regular amounts while arranging medical advice; do not force fluids if you are vomiting or have been told to restrict them. Avoid further exercise and avoid taking medicines for pain without checking that they are appropriate for you. A clinician may assess urine, blood tests, hydration, and kidney function.

Seek urgent medical care for dark or reduced urine, severe muscle pain or swelling, pronounced weakness, confusion, fainting, repeated vomiting, or trouble breathing. After intense exertion in heat, do not wait for symptoms to become clearer if you feel significantly unwell. Emergency help is appropriate for collapse or altered consciousness.

Ask what may have triggered the muscle injury, which tests are needed, how much activity and fluid are suitable, which medicines to avoid, and when it is safe to resume exercise.