3. DEFINITION: Describes the percentages of fat, bone, muscle, and fluid that make up body weight Factors that affect a person’s body composition: Heredity Diet Exercise Occupation

4. Body Composition Two people who have the same height and the same body weight may look completely different from each other because they have a different body composition

5. Healthy Body Fat Percentages MALEFEMALE Adults 13-17 % 20-25% Adolescents10-20% 15-25% Why are adolescent recommendations different than those of adults? Kids grow and develop at different times Why are boys and girls recommendations different? Boys and girls have different hormones that effect their body composition and girls have 1/3 less muscle fiber than boys

6. Ways to Measure SKINFOLD MEASUREMENTS: Measures layer of fat under skin (± 3% error) BIOELECTRIC IMPEDANCE: Estimates amount of fat by the amount of electrical current needed to travel through body (± 3 %)

7. Ways to Measure (cont) Hydrostatic Weighing: Estimates fat by measuring water displacement (± 1.5%) Body Mass Index (BMI): Describes appropriateness of height and weight (does not measure body fat) (± 5-6%)

8. ASSESSMENT OF BODY COMPOSITION Doctor’s Office BMI Personal Trainer Bioelectric Impedance Hydrostatic Weighing Skinfold measurements

9. Benefits of Improved Body Composition Decrease levels of body fat that cause obesity Decrease risk of coronary heart disease Decrease chances for stroke Decrease chances for diabetes Lower blood pressure Lower Cholesterol levels