Intense exercise routines are leading to cases of a potential life-threatening complication called rhabdomyolysis, according to health experts.
The condition causes a breakdown of muscle tissue, releasing a damaging protein into the blood and possibly damaging the kidneys.
Muscle pain, weakness and severe swelling after intense exercise may warrant a trip to the doctor.
It could lead to permanent kidney damage and needing lifelong dialysis.
Experts say staying well hydrated can help prevent rhabdo, but your best bet is knowing your limits.