Perhaps the least obvious among the risks of not exercising is the impact on your joints and bones. A frequently exercised (and stretched) joint is flexible, while an unused one is weaker, less elastic and more prone to nasty tears. Muscle shortening, which goes hand in hand with this, can further the problem by creating involuntary imbalances in the body that causes injuries over time. As for the bones, elderly women in particular are susceptible to bone brittleness. Part of this has to do with calcium intake, but exercise is another key component in keeping the bone mass intact. Simply put -- use it or lose it!