Rhabdomyolysis in runners: warning signs and next steps

A sudden increase in distance, speed work, hills, heat, or long training without adequate recovery can place unusual stress on muscle. Injury, illness, and certain medicines can add to that stress. Damaged muscle releases proteins and minerals into the blood, which may affect the kidneys and fluid balance. Severe muscle tenderness, swelling, weakness, cramps, or exhaustion may appear during or after a run. Dark urine is a warning sign, but its absence does not rule out the condition.

Routine soreness tends to be familiar and improves gradually. Rhabdomyolysis can feel more intense, limit normal movement, or worsen instead of easing. For a comparison with common post-exercise discomfort, see [Muscle Soreness After Exercise](/symptoms/muscle-soreness-after-exercise/).

Stop running, move to a cool place, and arrange prompt medical assessment. Record the workout details, heat exposure, fluid intake, supplements, medicines, and when symptoms began. Sip fluids if you are fully alert and can keep them down, unless a clinician has told you to restrict fluids; do not force fluids if vomiting or confused. Avoid further exercise, alcohol, and unapproved pain medicines until assessed. Clinicians may check muscle enzymes, kidney function, minerals, urine, and hydration status.

Use emergency care for cola-coloured urine, sharply reduced urination, severe swelling or pain, fainting, confusion, chest symptoms, breathing difficulty, or repeated vomiting. Prompt assessment is also appropriate for profound weakness or symptoms that are escalating after a demanding run. Do not use the ability to walk, or a normal-looking urine sample, as proof that the kidneys are unaffected.

Ask which results show recovery, when you can resume easy running, how training should be rebuilt, and whether heat or hydration changes matter for you. Ask whether any medicine or supplement may have contributed and whether follow-up testing is needed before returning to hard sessions.