The topic of "no pain, no gain" is one that arises almost daily in my practice. Is pain during exercise appropriate? When is it too much, leading to muscle strain and injury?

We tend to follow a simple pain number scale (0-10) for determining the "allowable" amount of pain with exercise at my office. If you consider the exercise pain free, you score it a 0, moderate pain is a 5 and excruciating pain is a 10. For a healthy, pain-free population, exercise should not elicit pain other than the sensation of burning due to muscle fatigue. This is a normal sensation and indicates minor muscle "damage" that enables muscle growth, strengthening and repair with the appropriate rest between workouts. This type of pain goes away within seconds of stopping the exercise.

During rehabilitation of an injury where there is baseline pain present prior to initiating the workout, we allow up to moderate pain but no greater than a 7. For anyone, if the pain is described as sharp or shooting, it is suspect for impending injury. At that point, the exercise intensity (weight) should be reduced. If pain remains still, the exercise should either be modified to a smaller range of motion or stopped altogether. Similarly, if pain intensity increases more and more with each repetition, the exercise is not being done properly or the intensity is too high.

Another "normal" pain you may feel occurs 1-2 days after your workout. In the medical community this is termed DOMS, short for delayed onset muscle soreness. This muscle pain creeps up 12-48 hours after performing a strenuous activity and that lasts a few days. DOMS is a normal response to increased exertion to which the body is not accustomed. Once your muscles get familiar with the movement patterns, the same activity at the same intensity will no longer result in soreness. Although the soreness is, well, sore, it is not a cause for concern and it serves as a reminder of the great workout your body had!  It can also be perceived as the same type of "good hurt" you may have experienced after an intense deep tissue massage. Both allow you to feel muscles that you never knew you had!

Pain is the body's warning signal that injury is occurring or about to occur so it should never be ignored. It is important to become familiar with identifying the "good pain" associated with muscle growth and strengthening or healthy stretching and differentiating this sensation from a "bad pain." Our bodies are pretty amazing and will tell us what we need to do; it's up to us to listen.

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