Chapter Exercise Prescription for Weight Management Dixie L. Thompson C H A P T E R

Figure 12.1

Factors Contributing to Increased Body Fat in Adults Decreased resting metabolic rate (RMR) Natural loss of muscle mass with aging Possibly accelerated due to decreased activity More sedentary lifestyle Unadjusted eating patterns

Etiology of Obesity: Genetics Versus Lifestyle Genetics 30% to 70% of the interindividual variation. May play a role in total fat and visceral fat. Only a small percentage of population would have genetic obesity due to reasons other than environment. Our genetic code has not changed substantially in the last few decades. Therefore, genetics is likely not the culprit of the obesity epidemic. (continued)

Etiology of Obesity: Genetics Versus Lifestyle (continued) Lifestyle: positive caloric balance Food intake Types of food eaten Dietary fat is stored more readily as adipose tissue and contains twice the kcal as protein or CHO Daily energy expended Does low PA lead to obesity, or does obesity lead to low PA?

Figure 12.2

Maintaining a Healthy Weight Establish an estimate of daily caloric need using existing formulas Equations are based on these factors: RMR being proportional to body size RMR decreasing with age Muscle being metabolically more active than fat Additional equations exist when FFM is known Why is sex unimportant in an equation such as this?

Common Steps to Promoting Lifestyle Change Reduce total kcal intake Diet of 800 to 1,500 kcal/day May reduce RMR Reduce fat intake Increase physical activity Change eating behaviors Eat for physiological rather than psychological or social reasons

ACSM Recommendations for Weight Management Set a goal for a reduction of no more than 2 lbs per week Reflects a weekly deficit of 3,500 to 7,000 kcal Limit fat intake to <30% of total daily intake Aim for minimum 150 minutes of physical activity per week 200 to 300 minutes per week will likely produce more benefits

Exercise Prescription for Weight Management Frequency of 5 to 7 days per week Intensity of 40% to 75% VO 2 max Duration of 45 to 60 minutes Type of exercise Aerobic to facilitate caloric deficit Resistance training to help maintain fat-free mass

Behavior Modification for Weight Loss and Weight Maintenance Keep records Documents problem areas of food intake Documents social cues to eating Makes eating a cognitive process Plan meals and snacks Fast food equates to higher fat and calorie intake Establish a support system (continued)

Behavior Modification for Weight Loss and Weight Maintenance (continued) Define behavior as well as outcome goals Plan a reward Avoid self-defeating behaviors Combine moderate caloric restriction and exercise Change unhealthy eating patterns Commit to lifelong maintenance

Gimmicks and Gadgets for Weight Loss The only proven long-term solution to weight management is permanent lifestyle behavior Gimmicks may reduce weight in the short term, but often it is water weight that is lost (part of fat-free mass), not fat mass In the long term, some gimmicks may be harmful Spot reduction is not a reality Weight loss occurs throughout the body and no one exercise promotes fat loss from any area

Eating Disorders Clinical diagnoses Anorexia nervosa Purposeful maintenance of body weight at less than 85% for expected weight and height Fear of gaining weight or fat Unhealthy body image Bulimia nervosa Large amounts of food taken in followed by purging Binge eating disorder Large amounts of food taken in without purging

Disordered Eating A subclinical condition May lead to a clinical eating disorder Often emotional eating rather than physical hunger Most common in young women or female athletes

Strategies for Gaining Weight Encourage fat-free gain rather than fat gain Resistance training is a necessity Increase kcal intake by 200 to 1,000 per day Increase healthy snacks Consume complex carbohydrate and high- quality protein Intake of >1.7 g per kg per day is not warranted; reasonable only in intense resistance training