Grueling physical training used to be something only encountered in the military, and used as much for shaping the psyche as for shaping the body. In recent years, we have seen a rise in extremely demanding exercise regimens geared toward the general public. Workouts like CrossFit, P90X, and other high intensity training have become very popular. CrossFit, especially, brings with it a culture of "never too much" and working well beyond exhaustion. I've never understood the appeal of a workout that leaves you vomiting, but I thought it was just because I am not a big fan of hard work.
My instincts may be right. This article from the New York Times describes the rise of rhabdomyolysis among people participating in punishing workouts. Rhabdomyolysis, or "rhabdo" as it's known among healthcare workers and high intensity athletes, is a condition in which your muscle cells basically puke out their contents. It is a life-threatening condition, and people with rhabdo require a hospital stay to rescue their kidneys.
Is your workout really worth two kidneys?
"Pain is weakness leaving the body." This can be very true for proper physical training. The root principle of strength training is to push the muscles beyond what they can do. This causes microtrauma of the tissue, which stimulates it to build back stronger. Carefully exceeding your body's abilities is key to making gains. The important word is "carefully." When people are in a class or trainer situation and feel social or personal pressure to complete the workout no matter what, they put themselves at risk of blowing so far past the body's limit, they trigger rhabdo.
It isn't the workouts themselves that worry me, it's the culture; the culture that says physical toughness is a critical skill, that destruction and pain are admirable pursuits, and that pacing, graduated efforts, and respecting one's limits are for the weak. What does this masochistic Darwinism say about us?
I oppose fundamentalism of any kind: religious or ideological. "All or nothing" is not an attitude that embraces diversity or is kind to a flawed humanity. Your body is made to follow the Middle Way: some food, some work, some play, some rest. Your body has safeguards for surviving extraordinary circumstances; they are not meant to be engaged on a regular, repeating basis. Your body sends you pain signals primarily as a warning that tissue damage is happening. If you feel a little pain, there's a little damage. If you feel a lot of pain, there is a lot. To exercise is to care for your body. Cherish the wonderful body that is carrying you through your life, respect its wisdom and honor its limits.