ABC News Good Morning America—August 8, 2013
Web entrepreneur Matt Lombardi said he just wanted to get into shape -- but it took only one session of the popular P90X workout series to send the 29-year-old to the hospital with rhabdomyolysis, a relatively rare condition he said his doctors told him occurs when muscle tissue breaks down to such an extent that toxins released into the blood stream can damage the kidneys.
Fortunately, after a five-day hospital stay, the problem subsided and doctors told Lombardi there probably wouldn't be any lingering effects. However, Lombardi's experience may underscore the hazards of high-intensity interval training, or HIITS, an exercise and weight-loss trend that involves alternating bouts of extremely vigorous exercise with brief rest periods.
HIITs programs have exploded in popularity in the past few years. The P90X DVD series has sold more than 4.2 million copies, according to Beach Body, the company that distributes the program. Insanity, also by Beach Body, has sold more than 2 million copies. Cross Fit, another popular HIITs workout system, has, according to its website, more than 5,000 affiliate gyms in North America with thousands more on other continents.
Experts said problems can arise when exercisers try to do too much, too soon.
Rather than traumatic injuries like broken bones and stress fractures, he said, high-intensity exercisers tend to rack up muscle sprains and tendon strains, particularly of the calf, chest and shoulder, the result of overusing explosive movements and heavy weights.
"I think these programs are quite good, but if someone goes from couch to full throttle without any preparation, there's a good chance they're going to get hurt," he said.
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