David Keisler

David Keisler

If you are going to start an exercise program primarily to lose weight you might want to realize that most who have weight loss as a primary goal may become disappointed. Significant loss of weight because of exercise is not common. In fact, many participants in a recent study did not shed as many pounds as hoped for, and a few even gained weight.

In a recent article in the American Journal of Clinical Nutrition, 171 sedentary individuals were followed for over six months. Initially, body weight, resting metabolic rate, fitness level, food intake and energy expenditure were measured before and then after the study.

One group was asked to continue their usual sedentary ways without an exercise program. Another group was asked to exercise three times a week by using either a treadmill or an exercise bike. Half of this second group was programmed to burn 8 calories per kilogram of body weight for a total of about 700 calories a week. The other half of the exercisers were set up to burn 20 calories per kilogram of body weight, or about 1,760 calories a week. Each group was followed for 6 months and allowed to eat as much food as desired with no dietary restrictions.

The results were interesting. Naturally, the sedentary control group did not lose weight. However, 66% of the 700 calorie group and 90% of the 1,760 calorie participants lost less weight than expected. It was noted that most exercisers ate more during those 6 months. Some took in only about 90 additional calories daily and others as much as 125 calories a day.

Exercise has been recommended for weight management, however exercise increases energy expenditure and therefore increases appetite. A small percentage of participants in this study gained weight.

Most participants eat more after exercise, even if that is only a few calories, and therefore significant weight loss should not be expected. If calories are burned because of exercise, then weight loss should occur only if additional calories are not consumed. Some participants reward themselves with additional food intake after exercising. In the above study, participants who avoided those additional calories lost weight.

In summary, the benefits of a regular exercise program do not include significant weight loss. However, decreasing the risk of vascular disease and type 2 diabetes along with favorable blood pressure recordings are reasons to keep moving for at least a total of 150 minutes a week. Do not let the lack of achieving significant weight loss through exercise keep you on the couch. Remember: Sitting is the new smoking!

David Keisler is a gastroenterologist and internist in Aiken.