Energy Balance and Body Composition

1. Energy Balance and Body Composition

2. Energy Balance • Metabolism • Daily Activity • Exercise-type • and intensity • Thermal effect • of meals • Type of energy • Amount at • one time • Timing of meals • Energy stored • in body Energy INTAKE Energy Expenditure

3. Energy intake Type of energy: ie..Quality of energy intake Carbohydrate vs Fat Amount at one time: i.e. Quantity of energy intake All at once vs small amounts Timing of Meals: Early vs late Energy Stores; Glycogen reserve in Liver and Muscle

4. Energy In: The kCalories Foods Provide • Food Intake; Regulated by • Appetite initiates eating through the sight, smell, thought or taste of food. • Hunger is the feeling that motivates us to eat and is controlled by the hypothalamus. • Satiation is the feeling of satisfaction and fullness that causes us to stop eating. • Satiety reminds us not to eat again until the body needs food.

6. Energy In: The kCalories Foods Provide • Food Intake • Overriding Hunger and Satiety • Stress eating is eating in response to arousal. • Cognitive influences such as perceptions, memories, intellect, and social interactions • Sustaining Hunger and Satiety • Protein is the most satiating. • Complex carbohydrates are satiating. • High-fat foods stimulate and entice people to eat more.

7. Energy In: The kCalories Foods Provide • Food Intake • Message Central—The Hypothalamus • Integrates messages about energy intake, expenditure, and storage

8. Energy Expenditure Metabolism: Age, gender, body composition, diet, exercise, stress, disease, drugs Daily Activity: Sedentary daily life activities vs busy or active life Exercise: Aerobic vs Resistant training, Duration and intensity Thermal Effect of Meals:Type and Number of Meals Physical Activity

10. Energy Out: The kCalories the Body Expends • Components of Energy Expenditure • Basal Metabolism (basal metabolic rate, BMR) • 2/3 of energyexpenditure For most sedentary individuals • Supports the basic processes of life • Resting metabolic rate (RMR) is a measure of energy slightly higher than BMR.

12. Energy Out: The kCalories the Body Expends • Components of Energy Expenditure • Basal Metabolism - Factors affecting BMR • Aging slows BMR • Height – the taller, the higher the BMR • Growth increases BMR. • Body composition (lean body mass increases BMR) • Fever increases BMR. • Stress increases BMR. • Environmental temperature - both heat and cold raise BMR

13. Energy Out: The kCalories the Body Expends • Components of Energy Expenditure • Basal Metabolism - Factors affecting BMR • Fasting/starvation slows BMR. (Dieting) • Malnutrition slows BMR. • Hormones • Thyroid hormones can increase or decrease BMR. • Premenstrual hormones can increase BMR. • Smoking increases BMR. • Caffeine increases BMR. • Sleep slows BMR.

14. Energy Out: The kCalories the Body Expends • Components of Energy Expenditure • Physical activity • Most variable and changeable • Voluntary • It can be significant in weight loss and weight gain. • Duration, frequency and intensity influence energy expenditure.

15. Energy Out: The kCalories the Body Expends • Components of Energy Expenditure • Thermic effect of food (TEF) is estimated at 10% of total energy intake and involves digestion and absorption. • Carbohydrate 5-10% • Fat 0-5% • Protein 20-30% • Alcohol 15-20% • Adaptive thermogenesis is the adjustment in energy expenditure related to environmental changes.

16. Energy Out: The kCalories the Body Expends • Estimating energy requirements is affected by many factors. • Gender – men generally have a higher BMR • Growth – BMR is high in people who are growing • Age – BMR declines as lean body mass decreases • Physical activity – Activities are clustered by intensity and vary considerably • Body composition and body size – taller people have more surface area and heavier people have higher BMRs

17. Body Weight, Body Composition, and Health • Current weight standards use height and weight data and do not take body composition into consideration. • These may be misleading.

18. Overweight (BMI > 25)‏ Obesity (BMI > 30)‏ Severe Obesity (BMI > 40)‏ 1999 to 2000 64.5 30.5 4.7 1988 to 1994 56.0 23.0 2.9 1976 to 1980 46.0 14.4 No Data Changes 1980-2000 Increase in Prevalence (%) of Overweight (BMI >or= 25), Obesity (BMI >or=30) and Severe Obesity (BMI >or=40) Among U.S. Adults.

20. Body Weight, Body Composition, and Health • Defining Healthy Body Weight • The Criterion of Fashion • Society values change over time. • Perceived body images • The Criterion of Health • Good health supercedes appearance. • Longevity is a criterion.

22. Body Weight, Body Composition, and Health • Defining Healthy Body Weight • Body mass index (BMI) measures relative weight for height. • Underweight is a BMI below 18.5. • Overweight is a BMI above 25. • Obese is a BMI above 30.

27. Body Weight, Body Composition, and Health • Body Fat and Its Distribution • Fat Distribution • Intra-abdominal fat around abdominal organs may be critical. • Central obesity is excess fat around the trunk of the body. It is also called abdominal fat or upper-body fat. • Associated with increased risks

28. Visceral Abdominal Fat • Fat mainly around the waist is more likely to develop health problems than fat mainly in hips and thighs. • This is true even if BMI falls within the normal range.

30. WM Waist Management

32. Waist Circumference • To measure waist circumference, place a tape measure around bare abdomen just above hip bone. • Be sure that the tape is snug, but does not compress your skin, and is parallel to the floor. Relax, exhale, and measure waist.

33. Body Weight, Body Composition, and Health • Body Fat and Its Distribution • Waist Circumference Women with a waist measurement of more than 35 inches Men with a waist measurement of more than 40 inches

34. Body Weight, Body Composition, and Health • Body Fat and Its Distribution • Measures of Body Composition(%BF) • Monitoring changes over time is important. • Fatfold measures • Hydrodensitometry • Bioelectrical impedance

36. Body Weight, Body Composition, and Health • Health Risks Associated with Body Weight and Body Fat • An appropriate weight for an individual depends on many factors which include body fat distribution, health history and current state of health. • Health Risks of Underweight • Cannot handle medical stresses • Menstrual irregularities and infertility • Pregnancy problems • Osteoporosis and bone fractures

38. Health Risks Associated with Body Weight and Body Fat Diabetes Hypertension Cardiovascular disease Sleep apnea Osteoarthritis Some cancers Gallbladder disease Kidney disease Respiratory problems – Pickwickian syndrome Complications in pregnancy and surgery Body Weight, Body Composition, and Health

39. Body Weight, Body Composition, and Health • Health Risks Associated with Body Weight and Body Fat • Cardiovascular disease and obesity have a strong relationship. • Diabetes and obesity have a strong relationship. • Insulin resistance and obesity have a strong relationship.

40. Eating Disorders

42. Eating Disorders • Many individuals, including young females, suffer from eating disorders. • These include anorexia nervosa, bulimia nervosa and binge-eating disorders. • The causes include a combination of sociocultural, psychological, and perhaps neurochemical factors. • Athletes are among the most likely group to develop eating disorders.

43. The Female Athlete Triad • Disordered eating habits can develop. • Desire to improve performance • Enhance aesthetic appeal of their performance • Meet unsuitable weight standards

45. The Female Athlete Triad • Osteoporosis • Stress hormones compromise bone health. • Stress fractures are common bone injuries. • Adequate calcium is recommended.

46. Preventing Eating Disorders in Athletes • Follow USDA Food Guide for food servings. • Eat frequently, especially healthy snacks. • Establish a reasonable weight goal. • Allow reasonable time to achieve the weight goal. • Join a weight maintenance support group.

47. Anorexia Nervosa • Characteristics of Anorexia Nervosa • Self-starvation – tremendous self-control to limit eating • Physical consequences are major and life threatening. • Treatment is multidisciplinary • Food and weight • Relationships with self and others

48. Bulimia Nervosa • Characteristics of Bulimia Nervosa • Binge eating – lack of control over eating, excessive kcalories from high-fat, low-fiber and high-carbohydrate foods eaten all at once • Purging – cathartic and/or emetic • Treatment of Bulimia Nervosa • Weight maintenance • Regular exercise • Counseling

49. Negative self-perceptions Restrictive dieting Purging Binge eating Stepped Art Fig. H8-2, p. 275

50. Binge-Eating Disorder • An unspecified eating disorder sharing some of the characteristics of anorexia nervosa and bulimia nervosa yet does not meet the criteria for diagnosis. • Lack of self-control over eating with binges • Consuming large quantities of food, eating quickly, feeling uncomfortably full, eating alone, and feeling disgusted or guilty • Marked distress • Occurrence of two times per week for six months • Not associated with compensatory behaviors