The benefits of regular exercise are plentiful. Both aerobic and anaerobic exercise are proven to help control weight, increase stamina, boost the immune system and improve mood. How skipping exercise affects your body depends on the length of time you have taken off, your current fitness level and your genetic history.
Skipping exercise infrequently will not negatively affect your health. In fact, taking one or two days off a week allows for muscle recovery and decreases your chance of injury.
If you continue to eat the same amount of calories, but skip your exercise routine, you will gain body fat. Where you store body fat depends on your genetic history. According to Claude Bouchard, author of "The Genetics of Obesity," you can tell where your body will store fat by where your parents' bodies store fat. Keep in mind that excess weight around the hips and thighs is less of a health risk than excess belly fat, which is an early predictor of high blood pressure and diabetes.
Skipping exercise results in muscle loss after two weeks of inactivity. When you exercise regularly, your body produces key enzymes that help your muscles grow and maintain themselves. When you stop, it takes your brain about two weeks to realize it no longer needs to produce these enzymes. Regaining muscle takes half the time that it takes to lose it. According to Wayne Westcott, fitness research director at the South Shore YMCA in Quincy, Massachusetts, if you stop exercising for two months, it should only take one month to get back to where you started.
A sudden stop in exercise can lead to extreme psychological changes. If you regularly exercise, you're accustomed to the release of chemicals in the brain that promote feelings like happiness and relaxation. When you stop exercising, your brain stops producing these chemicals. As a result, you may feel anxious, irritable, and have trouble sleeping for a week or two after you stop exercising.