by Dr. Gabe Mirkin, M.D.
Your body is a finely-tuned machine that requires constant movement. A study from the University of Missouri shows that as soon as you start to exercise less than you normally do, your body changes, causing blood sugar and insulin levels to rise; and you develop changes that eventually can lead to diabetes and a heart attack (Med Sci Sports Exerc, February, 2012;44(2):225-31). The American Heart Association recommends that you take at least 10,000 steps per day, equivalent to 30 minutes of walking or slow jogging. The average American takes fewer than 5,000 steps per day.
The results of this study should encourage you never to stop exercising. When blood sugar levels rise too high, sugar sticks to the outside membranes of cells. Once there, it can never be removed. The sugar is converted eventually to sorbitol, which destroys the cells to cause every known side effect of diabetes: blindness, deafness, heart attacks, strokes, loss of feeling, impotence, kidney failure and so forth.
Resting muscles are dead. They need insulin to draw sugar from the bloodstream into their cells; even then, they do it very poorly. On the other hand, contracting muscles can draw sugar from the bloodstream without needing insulin. This blood-lowering effect is maximal when you are exercising and for up to an hour after you finish. Then it tapers until it completely disappears after 17 hours.
So 17 hours after you finish exercising, your blood sugar starts to rise higher than normal after you eat. Your arteries will not be damaged by high blood sugar levels after just one day of not exercising. However they will be damaged if you continue to avoid exercise.
When your blood sugar levels start to rise higher than normal, your pancreas releases more insulin in an effort to lower your high blood sugar levels. So your blood insulin levels rise. High insulin levels constrict arteries leading to your heart to cause heart attacks. The authors showed that insulin levels rise after just one day of reduced exercising.
Recent data show that the more intensely you exercise, the greater the ability of muscles to prevent blood sugar levels from rising too high. You help to prevent diabetes and heart attacks by contracting your muscles. Keep on moving.