What seemed like aches for Linda Pickering, 17, after a spin class quickly turned into not being able to walk.
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Her mom Valerie realized this was more than sore muscles.
"She was in agony and nothing was helping," Valerie said. "Within 48 hours her kidneys had failed."
It led to an extended hospital stay, but Linda will make a full recovery. It could have been even worse.
"There's as much as a five percent chance of death with rhabdomyolysis. If your kidneys go, you're in bad shape," Dr. Noam Rosines at Village Emergency Centers said.
Dr. Rosines said extreme exercise can lead to rhabdo. That means muscles are breaking down, releasing toxins into the blood.
It could lead to permanent kidney danger and needing lifelong dialysis.
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So how can you tell normal soreness from this dangerous condition?
"It shouldn't be associated with extreme fatigue to where you feel like you can't get out of bed," Rosines said. "The other thing you'll notice as it progresses, you'll get darker urine."
Experts say staying well hydrated can help prevent rhabdo, but your best bet is knowing your limits.
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