Is it possible to do too much exercise? Given the fact that most Americans do not meet minimum recommendations for physical activity, doing too much may not seem like a problem. To be sure, the biggest exercise problem most people face is not getting enough. But doing too much exercise can have negative effects.
What constitutes too much exercise? First, let’s review the recommendations. The Physical Activity Guidelines for Americans call for 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic physical activity per week and do strengthening exercises that involve all major muscle groups at least two days per week. This recommendation can be met by a 30-minute brisk walk five days per week or longer, more vigorous workouts two days per week.
Many people do more than this, often an hour or more of vigorous exercise each day. While this may seem like a lot of exercise, these individuals built up to these workouts over months or even years. But they almost certainly started out with shorter, less intense exercise sessions. As their strength and endurance improved, they increased the time and intensity of their training. Even now, they likely structure their workouts in order to allow recovery time. For example, a runner might do a long run one day followed by a shorter run the next. Weight lifters usually alternate muscle groups on different days: chest exercises on one day, arms the next and so forth.
When beginning an exercise program, it is smart to start slowly and work your way up to longer, more intense sessions. In fact, a common occurrence is that new exercisers do too much too soon. This can lead to severe muscle soreness that limits the ability to exercise on the following days and, in some cases, injury. At the very least, a negative experience with exercise can cause a person to stop exercising. One of the most common reasons people quit an exercise program is injury or soreness early on. Taking it slow in the beginning can help you avoid these problems.
Even athletes with years of training experience can overdo it. Athletes are known for long, intense training sessions to develop the high levels of strength and endurance required to be competitive. But training too intensely or for too long can have negative effects. This phenomenon is called overtraining and, for some athletes, can be as big a problem as not training enough. Overtraining can lead to poor immune function, reduced motivation and fatigue, all of which can have a serious impact on performance.
Many competitive athletes intentionally do less in the days and weeks leading up to a big event. This is a process called tapering and it involves reducing training time and intensity, even including a rest day. This allows the muscles to recover and reduces the risk of injury. While many athletes – and coaches – think that a hard workout or practice before a big game is a good idea, failure to taper can lead to poor performance.
If you are like most people, you are probably not doing too much exercise. But you should make small increases in your time and intensity to reduce the chance of injury. If you are training for a run such as a 10k, you should plan a rest day before the race. And while more exercise is generally better for health and fitness, keep in mind that doing too much can have the opposite effect.
Brian Parr, Ph.D., is an associate professor in the Department of Exercise and Sports Science at USC Aiken where he teaches courses in exercise physiology, nutrition and health behavior. He is a member of the American College of Sports Medicine and is an ACSM certified clinical exercise specialist; his research focuses on physical activity in weight management and the impact of the environment on activity and diet. Parr lives in Aiken with his wife, Laura, and sons Noah, Owen and Simon.