As if we needed more of a reason to avoid working out, one man claims that just a single session of the high intensity workout system P90X sent him to the emergency room with kidney failure.

Matt Lombardi, an internet entrepreneur, just wanted to get back in shape after putting on twenty pounds while launching the sports website College Spun. After completing the first day of the P90X regimen, which is the “Chest & Back” portion, Lombardi experienced pain and discomfort. He chalked up that initial discomfort to the intensity of the workout. However, as he writes in his first-hand account published on College Spun, things soon took a terrifying turn:

“Thursday morning, things got real. When I got up to go to the bathroom, I noticed that my urine looked like Coca-Cola. In an attempt to self-diagnose (usually a bad idea), I Googled my symptoms. Ten seconds later, I knew I had “rhabdo” and that I was in serious trouble.”

The condition that Lombardi discovered is known as rhabdomyolysis, which occurs when skeletal muscle tissue breaks down and releases toxins into the body. The increased level of toxins can lead to kidney failure if not treated promptly.

While the condition often occurs after “crush” injuries, as often occur during building collapses, the round of P90X was apparently intense enough to trigger it. However, that is not to say that the exercise program alone is to blame. As Lombardi himself mentions, it is not uncommon for even well-honed collegiate athletes to develop the condition if they engage in strenuous exercise following a prolonged hiatus.

Regimens such as P90X have become fitness fads with their promise of quick and obvious results. While the idea of sporting the perfect beach body is often enough to lure the average joe from the couch, cases like Lombardi’s suggest that a more measured approach may be the better option. His story is one to keep in mind before trying to bust out 50 chin-ups when your normal routine includes lifting the remote to change the channel.