1. Body Composition

2. zBody composition involves all components of the body including: yFat mass yMuscle mass yBone mass yWater volume

3. Body Composition zWe’ve talked about muscle mass, so this section will focus on fat management.

4. Body Composition Abnormalities zObesity Epidemic y$33 billion weight-loss industry x$168 billion cost total y33.3% of all U.S. adults are obese - “an excess of body fat frequently resulting in a significant impairment of health” y~65% are sedentary y~25% of school-aged children are overweight or obese. y70% chance of early death.

5. Obesity zDefined as the percent body fat at which disease risk increases.

6. Obesity zAn excessive amount of body fat relative to body weight ynot synonymous with overweight.

7. Overweight and Obesity zBody Mass Index (BMI) is the most commonly used measure to define overweight and obesity. U.S. Department of Health and Human Services

8. The Epidemic of Overweight and Obesity zBMI is a measure of weight in relation to height. yWeight in Kg divided by height in meters 2 yWeight in pounds divided by height in inches 2, multiplied by 703. U.S. Department of Health and Human Services

9. The Epidemic of Overweight and Obesity zNational Institutes of Health Clinical Guidelines yoverweight in adults x BMI between 25 to 29.9 yobesity in adults x BMI of 30 or greater. zHealth risks are greater with a BMI > 25. U.S. Department of Health and Human Services

10. The Epidemic of Overweight and Obesity zThe risk of premature death increases with an increasing BMI. yThis increase in mortality tends to be modest until a BMI of 30 is reached. U.S. Department of Health and Human Services

12. The Epidemic of Overweight and Obesity zOverweight and obesity are increasing in both genders and among all population groups.

13. Body Composition zBecause BMI criteria do not take into account the composition of the excess weight, they are limited as indexes of obesity and may result in misclassifications of obesity.

14. Body Composition zOverweight vs Overfat zMetropolitan Life Insurance Height- Weight Charts

15. Two-component Model: zFat mass zFat-free mass

16. Criterion Referenced Standards: zCollege Aged Men Women zUnderfat < 3%<12% zHealthy Zones 3-20%12-30% zOverfat >20%> 30% zObese> 25%> 35%

17. Essential Fat zNecessary for normal physiologic function zMen = ~ 3% zWomen = ~ 12%

18. Non-essential fat zStored energy zAverage for college aged yMan = 12% yWoman = 12%

19. Average for College Aged Male = 15% Female = 24%

20. Sport specific body fat levels zMovement required zResistance to movement required Sprinter Maurice Greene

21. Body Composition zCombating obesity and eating disorders is not an easy task.

22. Body Composition zA positive energy balance leads to excessive weight gain and obesity yimproper diet yovereating yhormonal disturbances yphysical inactivity

23. Body Composition zLack of physical activity rather than overeating is a more common cause of obesity in children and adults.

24. Creeping Obesity z Food Intake z Activity Levels z Basal Metabolic Rate

25. Body Composition zObese individuals are invariably sedentary and many have had poor experiences with exercise in the past.

26. Overweight and Obesity zAmong women, the prevalence of overweight and obesity generally is higher in women who are members of racial and ethnic minority populations than in non-Hispanic white women. 7 zAmong men, Hispanics have a higher prevalence of overweight and obesity than non-Hispanic whites or non-Hispanic blacks. U.S. Department of Health and Human Services

27. The Epidemic of Overweight and Obesity zFor non-Hispanic men, the prevalence of overweight and obesity among whites is slightly greater than among blacks. U.S. Department of Health and Human Services

28. The Epidemic of Overweight and Obesity

29. zDisparities in prevalence of overweight and obesity also exist based on socioeconomic status. 7 yFor all racial and ethnic groups combined, women of lower socioeconomic status (income 130 percent of the poverty threshold). U.S. Department of Health and Human Services

30. The Epidemic of Overweight and Obesity zMen are about equally likely to be obese whether they are in a low or high socioeconomic group. U.S. Department of Health and Human Services

31. The Epidemic of Overweight and Obesity zThe overweight and obesity epidemic is not limited to adults. zThe percentage of young people who are overweight has almost doubled in the last 20 years for children aged 6-11 and almost tripled for adolescents aged 12-19. U.S. Department of Health and Human Services

32. The Epidemic of Overweight and Obesity zIn children and adolescents, overweight has been defined as a sex- and age- specific BMI at or above the 95th percentile for a reference population, based on Centers for Disease Control and Prevention (CDC) growth charts. U.S. Department of Health and Human Services

33. The Epidemic of Overweight and Obesity

34. Health Risks of Not Maintaining a Healthy Weight zThere is an increase in mortality associated with overweight and obesity. yApproximately 300,000 deaths a year in this country are currently associated with overweight and obesity. 29 U.S. Department of Health and Human Services

35. Health Risks of Not Maintaining a Healthy Weight zMorbidity from obesity may be as great as from poverty, smoking, or problem drinking. 20

37. Health Risks of Not Maintaining a Healthy Weight zIt is also important for individuals who are currently at a healthy weight to strive to maintain it since both modest and large weight gains are associated with significantly increased risk of disease. U.S. Department of Health and Human Services

38. Health Risks of Not Maintaining a Healthy Weight zFor example, a weight gain of 11 to 18 pounds increases a person’s risk for developing type 2 diabetes to twice that of individuals who have not gained weight, while those who gain 44 pounds or more have four times the risk of type 2 diabetes. 30 U.S. Department of Health and Human Services

39. Health Risks of Not Maintaining a Healthy Weight zA gain of 10 to 20 pounds resulted in an increased risk of coronary heart disease (which can result in nonfatal heart attacks and death) of 1.25 times in women 31 and 1.6 times in men. 32 zIn these studies, weight increases of 22 pounds in men and 44 pounds in women resulted in a increased coronary heart disease risk of 1.75 and 2.65, respectively. U.S. Department of Health and Human Services

40. Health Risks of Not Maintaining a Healthy Weight zWomen with a BMI of 34 or greater, the risk of developing endometrial cancer was increased by more than 6 times. 33 zOverweight and obesity are also known to exacerbate many chronic conditions such as hypertension and elevated cholesterol. U.S. Department of Health and Human Services

41. Body Composition zThe prevalence of hypercholesterolemia, hypertension, and Type II diabetes is, respectively 2.9, 2.1, and 2.9 times greater in overweight than in non- overweight persons.

42. Body Composition z Recent evidence indicates that “central obesity” is particularly problematic. z Abdominal fat is strongly associated with diseases such as CHD, diabetes, hypertension, and hyperlipidemia.

43. Body Composition Android and Gynoid Obesity

44. Body Composition zObesity is associated with a reduced physical working capacity.

45. Health Risks of Not Maintaining a Healthy Weight zOverweight and obese individuals also may suffer from social stigmatization, discrimination, and poor body image. U.S. Department of Health and Human Services

46. Body Composition zAt the opposite extreme, individuals with too little body fat tend to be malnourished.

47. Body Composition zOne disease associated with extremely low body fat levels is anorexia nervosa.

48. Body Composition zAnorexics have a relatively higher risk of xfluid-electrolyte imbalances, xosteoporosis and osteopenia, xbone fractures, xmuscle wasting, xcardiac arrhythmias, xsudden death, xedema, xand renal and reproductive disorders.

49. Body Composition zAnorexia nervosa is an eating disorder found primarily in females and is characterized by excessive weight loss.

50. Body Composition zAnorexics have extremely low body fat levels (8 to 13%), signs of muscle wasting, and less bone mineral content and bone density.

51. Health Risks of Not Maintaining a Healthy Weight zImportant consequences of excess weight as well as antecedents of adult disease occur in overweight children and adolescents. zOverweight children and adolescents are more likely to become overweight or obese adults. U.S. Department of Health and Human Services

52. Health Risks of Not Maintaining a Healthy Weight zType 2 diabetes, high blood lipids, and hypertension as well as early maturation and orthopedic problems are occurring with increased frequency. zA common consequence of childhood overweight is psychosocial specifically discrimination. 34 U.S. Department of Health and Human Services

53. System Dysfunction Associated with Obesity Obesity CardiovascularRenal Liver Reproductive Skeletal Respiratory Intestinal Pancreas Muscular Hormonal Metabolic

54. Hormones zHormones play an important role in regulating metabolism.

55. Hormones zThyroxine is extremely important in regulating resting metabolic rate. yUnderproduction of thyroxine can reduce RMR 30 to 50%.

56. Hormones zMay elevate RMR as much as 15 to 20%. yGrowth hormone, yEpinephrine, yNorepinephrine, yVarious sex hormones

57. Hormones zThese hormones increase during exercise and may be responsible for the elevation in resting metabolic rate after cessation of exercise.

58. Genetics zOnly 10% of children who had normal-weight parents were obese.

59. Genetics zThe probability of being obese is increased to 40% and 80%, respectively, if one parent or both parents are obese.

60. Genetics zAlthough these data suggest a strong genetic influence, they do not rule out environmental influences such as eating and exercise habits.

61. Genetics zApproximately 25% of the variability among individuals in absolute and relative body fat is attributed to genetic factors and 30% is associated with cultural (environmental) factors.

62. Psychological Issues zOverweight and obesity may be linked to psychological factors. zSome overweight and obese individuals use food and eating as a coping mechanism or defense mechanism.

63. Psychological Issues zCompulsive eaters may eat to cope with feelings of insecurity, anxiety, depression, loneliness, stress, and tension rather than to satisfy hunger.

64. Psychological Issues zIn this case, the individual needs to recognize the fact that he or she is eating compulsively, identify the underlying reasons for this behavior, and take steps to modify these behaviors.

65. Psychological Issues zEncourage clients with eating disorders to seek psychological counseling.

66. Fat Patterning z Sex related patterns z Genetic based patterns

67. Fat Storage zOne door room. yPrimary storage sites. ySecondary storage sites. yHyperplasia vs Hypertrophy

68. Hyperplasia vs Hypertrophy zObesity is associated with increases in both the number (hyperplasia) and size (hypertrophy) of fat cells.

69. Hyperplasia vs Hypertrophy zAn increase in fat cell number occurs rapidly during ythe last trimester in the womb through the first year of life, yaround ages 7-8, yand again during adolescence, ybut remains fairly stable in adulthood except in cases of morbid obesity.

70. Hyperplasia vs Hypertrophy zFat cells grow in size when excess fat is stored in the cells as triglycerides. zWeight gain in adults is typically characterized by the enlargement of existing fat cells, rather than the creation of new fat cells.

71. Hyperplasia vs Hypertrophy zSimilarly, caloric restriction and exercise are effective in reducing fat cell size, but not the number of fat cells.

72. Hyperplasia vs Hypertrophy zThe key to preventing obesity is to closely monitor the dietary intake and energy expenditure, especially during the adolescent growth spurt and puberty.

73. Hyperplasia vs Hypertrophy zThis could potentially retard the development of new fat cells and control the size of existing fat cells.