Woman Hospitalized After ‘Intense’ Workout Turns Her Urine the Color of ‘Coca-Cola’: ‘I Could’ve Died’

• Gemma Underwood was hospitalized after her muscles swelled and her urine turned a dark brown, comparing it to “Coca-Cola”

• The 41-year-old was diagnosed with rhabdomyolysis, a life-threatening injury caused by intense workouts that requires extensive rest

• She said she was “very scared knowing I could have died”

A woman was hospitalized with a severe reaction to working out that caused her muscles to balloon and her urine to turn dark.

Gemma Underwood, 41, is an orange belt in karate, and said she felt sore after an “intense” session in March, according to The Daily Mail. But the next morning, Underwood — who hails from the South Ayrshire in Scotland — woke up and couldn’t get out of bed. Her muscles were swelling and her urine was so dark she compared it to “Coca-Cola.”

She rushed to the emergency room, where doctors diagnosed her with rhabdomyolysis. It’s “a rare muscle injury where your muscles break down,” the Cleveland Clinic explains. It can also be fatal: It’s “a life-threatening condition that can happen after an injury or excessive exercise without rest.”

Related: Former High School Coach Accused of Forcing Students to Do 400 Push-Ups with No Break as Punishment

In Underwood’s case, her rhabdomyolysis was fueled by a lack of water. “Doctors said I wasn’t hydrated enough while doing an intense workout. I should have been drinking more water before,” she shared.

In rhabdomyolysis — or rhabado — “your muscles break down (disintegrate), which leads to muscle death. When this happens, toxic components of your muscle fibers enter your circulation system and kidneys.”

Underwood was hospitalized for five days, where she received intravenous fluid and needed a catheter. She’s now home, but said, “I’m very drained … treatment can take a few weeks or a few months depending on complications.”

Related: Tufts Lacrosse Players All Released from Hospital After Developing Life-Threatening Muscle Condition in Workout

“I am currently resting, no exercise at all for at least three weeks, and drinking plenty of fluids,” Underwood explained. “It’s really important to know the symptoms, which are muscle pain and weakness, and dark urine.”

“I was very scared knowing I could have died. Make sure you’re hydrated before any workout, it doesn’t matter how intense it is,” she cautioned. “It’s something that can happen to anyone.”

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