Achieving a Healthy Body Weight: Stigma of Obesity, Diets, and Weight Loss Interventions

1. chapter8 Fluid and Electrolyte Balance chapter 6 Achieving a Healthy Body Weight Prof Jennifer Broxterman, RD, MSc FN3373: Nutrition for Physical Activity Lecture 7 Author name here for Edited books

2. Interesting Facts • At any given time, it is estimated that at least 29% to 33% of the U.S. population is dieting (Calorie Control Council, 2007) • In adults aged 18 to 24 years, 20% of normal-weight individuals are dieting, while 45% to 67% of overweight and obese individuals are dieting (The Behavioural Risk Factor Surveillance System for the Centres for Disease Control and Prevention, 2003) • 23% of normal-weight adolescent girls use smoking as a way to lose weight (National Health and Nutrition Examination Survery, NHANES II, 2001)

3. Stigma of Obesity

4. Role of Diet & Exercise in Achieving a Healthy Body Weight

5. Criteria to Help Determine a Healthy Body Weight • Weight can be maintained without constant dieting or restraining food intake. • Weight at which health risks are minimized and good health is promoted. • Weight that promotes good eating habits. • Weight that allows one to participate in some type of physical activity. • Weight that can be accepted by the individual.

6. Criteria to Help Determine a Healthy Body Weight • Weight that allows optimal performance in the sport of one’s choice. • Weight that takes into consideration one’s genetic makeup and family history of body weight and body shape. • Weight appropriate for one’s age and level of physical development.

7. Body Weight in Athletics • Sports requiring a low body weight: • Ski jumping • Light-weight rowing • Wrestling • Cycling • Running • Equestrian • … • Weight gain in the off-season

8. Body Mass Index • Ratio of weight (in kilograms) to the square of height (in metres squared) • BMI = kg / m2

9. Figure 6.4

10. Figure 6.5

11. Health Effects of Obesity

12. Percentage Body Fat • Determinations of body fat percentage involve estimating the ratio of body fat to fat-free mass • Main methods used today: • Hydrodensitometry • Air Displacement Plethysmography (Bod Pod) • Dual Energy X-Ray Absorptiometry (DEXA) • Computed Tomography (CT) • Magnetic Resonance Imaging (MRI) • Bioelectrical Impedance Analysis (BIA) • Skinfold Measurements (Callipers)

13. Percentage Body Fat

14. Bod Pod http://www.nutritionrx.ca/services-rates/body-composition-testing/

15. Body Fat Distribution • Body fat distribution is assessed to determine where body fat deposits are located • Visceral abdominal obesity vs. subcutaneous fat • Android vs. gynoid shaped

16. Waist Circumference • Waist circumference (WC): • Easy to measure • Inexpensive • Specific measurement guidelines needs to be followed • To measure WC, locate the upper hip bone and the top of the right iliac crest. Place a measuring tape in a horizontal plane around the abdomen at the level of the iliac crest. • Before reading the tape measure, ensure that the tape is snug but does not compress the skin and is parallel to the floor. The measurement is made at the end of a normal expiration.

17. Figure 6.2

18. Weight Loss Interventions

19. Weight Loss in Athletes • Highest potential for successful weight loss: • Regular physical activity • Moderate energy restriction • Address lifestyle habits • Primary goal of a weight loss program: • Improve health by lowering body fat while maintaining or increasing FFM or muscle tissue

20. Successful Dieting Basics • Calories count • Composition of the diet is important • CHO, protein, fat, EtOH • Protein intake is important • Consider frequency of meals • Role of breakfast

21. Popular Diets • Starvation diets (“fasting”) • < 200 kcal/day • Very-low calorie diets • <800 kcal/day • Low-calorie diets • 1000 - 1500 kcal/day • Low-carb, high-protein diets • Atkins, South Beach, Paleo • RDA for CHO is 130 g/day • Popular or fat diets • Marketing, gimmicks, celebrity-endorsed, “miracle” foods

22. Popular Diets (continued) • Moderate Energy Restriction Diets • Moderate energy deficit (~300-600 kcal/day) through diet (~300 kcal/day), exercise (~300 kcal/day), or both (~600 kcal/day) • Low Energy-Dense Diets • Emphasises a diet high in unprocessed CHO (e.g. whole grains, legumes, beans, whole fruits, and vegetables) and lean protein sources (e.g. lean meats, fish, poultry, eggs/egg whites, low-fat dairy) • Volumetric weight-control plan

23. Maintaining a Healthy Body Weight

24. Components of a Behaviour Modification Program for Weight Loss or Weight Maintenance • Self-monitoring • Goal setting • Nutrition • Exercise • Stimulus control • Problem solving • Cognitive reconstruction • Relapse prevention

25. The National Weight Control Registry • Statistics: • Weight loss has ranged from 30 - 300 lb • Duration of successful weight loss has ranged from 1-66 years • Rapid vs. slow weight loss • Methods of weight loss: • Combination of diet + exercise • 45% lost weight on their own, 55% used a program • 98% modified their food intake in some way • 94% increased physical activity (walking)

26. The National Weight Control Registry • Strategies for weight maintenance: • Most participants consume a low-calorie, low-fat diet and participate in high levels of physical activity • Eating breakfast (80% eat breakfast every day; only 4% report never eating breakfast) • Monitoring energy and fat intake • Average ~24% kcal from fat • Limit certain high-fat foods, eat less food per meal, count grams of fat or calories, eat regular meals, adhering to the same diet regime throughout the week

27. The National Weight Control Registry • Strategies for weight maintenance: • Exercising daily • 90% reported exercising 1 hr or more per day on average • Weekly energy physical expenditures averaged ~2500 kcal/week for women and 3300 kcal/week for men • Weight loss maintainers engaged in significantly more high-intensity forms of physical activity and spent more minutes per week doing physical activity • Engaging in less sedentary activity • 62% watched < 10 hr of TV per week, with 36% reporting that they watched < 5 hr/week • Monitoring weight • Nearly 75% said they weighed themselves 1x/week

28. Weight Concerns of Athletes

29. Gaining Weight • Weight gain is a concern for many athletes • Ideal: achieve maximum gains in lean tissue and minimal gains in fat tissue • Must consume more energy than one expends • Successful weight gain should include: • A realistic weight gain goal • Adequate time to reach the goal • An increase in total energy intake, emphasizing high-quality proteins and carbohydrates • Incorporation of strength training into the exercise regimen • Use of a recovery mixture (fluid, electrolytes, CHO, protein) to promote rehydration, repletion of muscle glycogen, and muscle protein synthesis

30. Lean-Build Sports • Lean-build sports: a lean build is associated with successful performance & scoring • E.g. diving, track & field, dance, swimming, gymnastics, cross-country, bodybuilding • Weight concerns can lead to unhealthy behaviours and threaten an athlete’s health and performance • Poor eating habits • Increased risk for eating disorders • Increased risk for injury

31. Making Weight • Weight class sports: • E.g. horse racing (jockeys), wrestling, boxing, rowing • “making weight” = achieving a weight goal within a strictly defined weight class • Athletes commonly compete in a weight class lower than their typical BW • Primary concerns: • Weight cycling • Increased risk for eating disorders

32. Consequences of Unhealthy Weight Loss Practices & Recommendations for Athletes