Instead of suiting up in workout gear on Sunday, he found himself in a hospital gown hooked up to an IV drip that flushed his kidneys with more than nine liters of saline.As his creatine kinase levels—the amount of muscle protein broken down poisoning his blood stream— declined at the pace of a snail, he pulled out his phone to send a tweet to his fellow athletes. You can't understand what it's like unless you're on the inside.” 33-year-old Jennifer Wielgus, who’s been doing Cross Fit in Philadelphia for about a year. I knew what was coming was probably more than I could handle—and that not even my athletic background as a gymnast, weightlifter, running back or point guard would prepare me.“Back in the day, we used to give them shirts and the availability of the shirt ran out.”If most gyms struggle to have their patrons work hard enough, Cross Fit gyms struggle on the opposite end of the spectrum.
Uncle Rhabdo represents a character in the Cross Fit community and is short for rhabdomyolysis, a kidney condition most commonly induced by excessive exercise, according to Heather Gillespie, a sports medicine physician from UCLA.The defining characteristic of Cross Fit is the intensity. Its "prescription," as the guide states, is for “constantly varied, high-intensity, functional movements that will optimize physical competence in ten physical domains: cardiovascular and respiratory endurance, stamina, strength, flexibility, power, speed, coordination, agility, balance and accuracy.”The key to the high-voltage workouts is a digital clock that holds prime real estate in most Cross Fit facilities.Most of the workouts are time-based, meaning you don’t stop until the clock hits zero.“There’s pushing an athlete to the point of discomfort that is challenging,” says Joe Dowdell, founder and CEO of Peak Performance in New York City. Vomiting is a sign that you’ve hit a point when it’s just too much.”“Cross Fitters put up with burning muscles and overall strain so they’re used to 'bring it on, gimme more gimme more.' It gets hard to say oh, that’s pain, I need to stop” says David Geier, Jr., an orthopedic surgeon and the director of sports medicine at the Medical University of South Carolina.“I think the benefits of Cross Fit outweigh the risks—but the risks are real.”While all exercise can create injury, Geier sees more injuries with Cross Fit because of the high-speed, high-impact approach.