I have made no secret that I am against low-intensity weight training and steady state aerobics. There are numerous reasons, but in this post I want to focus on a new one. That is the concept of exercising to success.
I believe that the most important aspect to designing an exercise program is creating a pathway for success. This means working with your body and not against it. Leaving the gym feeling challenged and not defeated. Too many people leave the gym without challenging themselves or they run themselves to failure.
What is the evolutionary purpose for exercise? To chase down food or avoid being food. Since expending a lot of calories to chase down calories makes poor sense, our hormones reward brief and intense movements. When one engages in exercise that is long and excessive, the body releases the stress hormone cortisol which triggers insulin. That promotes fat storage, carb craving and suppresses growth hormone.
It is OK to train to failure occasionally. And low intensity work is great when recovering from illness or injury, however I strongly favor brief intense strength based workouts.
In the post Rambling Thoughts About Gym Survivorship, I mentioned that most of the people you see in the gym will fail to meet their goals. The body wants to be challenged and it wants to succeed. Lift something heavy or engage in a Tabata style high intensity workout and then leave. Do that 1-2 times a week. That is it.
At my gym, I’d say I am in better shape than 90% of the members. However, almost all the members work out longer and more days than me. When you push your body to failure time and time again on predictable exercise regiments, the body will optimize so the work out becomes less effective and then it will preemptively go to failure. By preemptively going to failure the body is attempting to protect itself from activity it sees as harmful. You may imagine yourself as the next Lance Armstrong, but your body thinks you are being chased by prey and you still haven’t escaped.
UPDATE (November 2013): I have altered my opinion slightly on this topic. It is fine to exercise to failure if it is done in a safe manner, but one needs much longer rest periods between workouts. For example a single HIT workout that lasts 15 minutes that results in total muscular failure might require 7-10 days of rest before returning to the gym. In this scenario most days are spent “resting to success”.