Home About ACSM

NEWS RELEASE

For immediate release:
December 10, 2001

ACSM RELEASES NEW POSITION STAND ON LOSING WEIGHT, KEEPING IT OFF
Replaces "Proper and Improper Weight Loss Programs" paper

INDIANAPOLIS--The American College of Sports Medicine (ACSM) has released a new Position Stand, Appropriate Intervention Strategies for Weight Loss and Prevention of Weight Regain for Adults, which addresses obesity and overweight in adults. Specific dietary and exercise recommendations are included. The paper also explores resistance exercise and pharmacotherapy in relation to weight loss and prevention of weight regain.

The statement, which is published in this month's issue of Medicine & Science in Sports & Exercise®, the official monthly journal of ACSM, addresses the significant public health problem of obesity. Noting that 55 - 60 percent of adults are overweight and 22 percent are obese, this paper chronicles an increase of nearly 37 percent incidence of these weight problems over about 12 years. In addition, an estimated $100 billion, or five to 10 percent of health care costs, is spent on obesity-related conditions annually. While providing detailed information about exercise interventions for losing weight and keeping it off, the paper specifically addresses the adult population, excluding sports and athletic performance and the child/adolescent population.

ACSM recommends that adults with a body mass index (BMI*) of more than 25 be identified as weight-loss candidates. Because body composition measurements vary widely and the level of body fatness associated with an increase in morbidity and mortality has not been established, ACSM recommends that clinical standards and standard measurement techniques be established. Beyond BMI, abdominal girth above 35 inches in women and 40 inches in men should be a signal for weight loss, because intra-abdominal fatness is associated with conditions that contribute to increased health risk. A weight loss of five to 10 percent of body weight is recommended at these levels, and even more long-term health benefits may be available to those who sustain weight loss of more than 10 percent.

In regard to dietary recommendations, the paper states the well-known fact that if energy needs exceed energy intake, weight loss will occur. Assuming a resting energy expenditure (REE) of one calorie per gram and a 2000-calorie per day, a realistic weight loss of one to two pounds per week can be achieved by reducing energy intake to 1000 - 1500 calories per day. The paper notes that very low calorie diets (VLCDs), used in conjunction with dietary supplements and requiring medical supervision, may increase the magnitude and rate of weight loss but probably will not improve long-term weight loss. Although stating that further research regarding optimal macronutrient composition is necessary, this paper notes that a 10 percent reduction in fat intake can have a significant impact on energy balance and body weight over the long term. Such reduction should be part of an overall reduction in energy intake.

An effective weight-loss program must include increased energy expenditure in addition to reduced dietary intake. The effect of exercise may differ according to gender and genetics, so these factors must be considered when making prescriptions for the amount, intensity and duration of exercise necessary for successful long-term weight loss. Research shows that approximately 4.5 hours of moderate intensity exercise that results in an energy expenditure of at least 2000 calories per week, in combination with reduced energy intake, will produce desirable results. This may not apply to all individuals, and even a three-hour per week exercise regimen may be difficult for some to establish and maintain. The paper recommends gradual progression and behavioral strategies to maintain these levels. Generally, moderate intensity exercise (55 - 69 percent of maximal heart rate) can be beneficial in weight management. Intermittent exercise, i.e. 10 - 15 minute sessions that accumulate to 30 - 40 minutes per day, seems to be as effective as continuous sessions. Lifestyle activities, on the other hand, may be a promising alternative to organized exercise, but further research is necessary to examine specific forms that can be helpful. It is necessary to increase daily activity to enhance caloric expenditure.

Addressing resistance exercise, the paper reiterates commonly known evidence of increased muscle strength and fat-free mass that results from consistent use of weights. But resistance exercise in combination with aerobic exercise does not typically enhance weight loss. Increased strength may facilitate the adoption of a more active lifestyle in sedentary overweight and obese individuals, thus leading to health benefits that may include weight loss and prevention of weight regain.

Pharmacological weight-loss treatments may be recommended as an adjunct to lifestyle modification interventions for obese individuals with other conditions. Drug treatment of obesity typically results in significant weight loss within six months. Despite limited weight loss resulting from drug treatment beyond this period, it may be effective for maintaining the initial weight loss. Sibutramine and Orlistat are the only two prescription drugs now approved for use by the United States Food and Drug Administration (FDA). Because it can contribute to an increase in blood pressure, patients with hypertension should avoid sibutramine. Orlistat prevents absorption of dietary fat, producing various predictable adverse events.

Certain behavioral recommendations are reviewed by the paper, including training in problem solving, social support, goal setting and stimulus control, as well as self-monitoring of eating and exercise behavior. Structured meal plans are recommended for weight loss programs. ACSM recommends that the public follow these general guidelines for losing weight and keeping it off: Consult with a trained healthcare professional, consider losing weight if BMI is 25 or above, reduce caloric and fat intake, exercise 2.5 - 4.5 hours a week, and use dietary supplements/weight loss drugs only under physician supervision.

The American College of Sports Medicine is the largest sports medicine and exercise science organization in the world. More than 18,000 International, National and Regional members are dedicated to promoting and integrating scientific research, education and practical applications of sports medicine and exercise science to maintain and enhance physical performance, fitness, health and quality of life.

NOTE: Medicine & Science in Sports & Exercise® is the official journal of the American College of Sports Medicine, and is available from Lippincott, Williams & Wilkins at 1-800-638-6423. For a complete copy of the Position Stand, visit ACSM online at www.acsm.org. To speak with a leading sports medicine expert on the topic, contact the Department of Communications and Public Information at 317-637-9200.

*Body mass index may be calculated with several formulas, including the following:
Divide WEIGHT IN POUNDS by HEIGHT IN INCHES SQUARED and multiply by 704.5