1. Body Composition

2. Body Composition The amount of fat, and fat-free mass in the body
Muscle
Bone
Body composition assessed in a variety of ways
Advantages for each method
Disadvantages for each method
Cost, availability, complexity, user/equipment error, quality/quantity of information, accuracy

3. Scale Weight Provides information on amount body mass
Advantages and disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

4. Height and Weight Charts
Provides information based on person’s height, weight, frame size
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

5. Body Mass Index Person’s weight divided by square of height
Provides information on disease risk
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

6. Circumferences Specific areas on body are measured with measuring tape
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

7. Waist to Hip Ratio Two circumferences: waist and hip
Measures provide CV disease risk information
Men: = “high risk”
Women: = “high risk”

8. Waist to Hip Ratio
Abdominal fat related to cardiovascular disease risk
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

9. Near Infrared Interactance
Method based on light absorption, reflectance
Probe is placed on body part, typically biceps
Probe emits infrared light, passing through tissue, reflected back into probe
Fat absorbs more infrared light than fat-free mass
The more light absorbed, the higher the fat mass

10. Near Infrared Interactance
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

11. Skinfolds
Specific instruments, “calipers” used to assess amount of fat under skin at specific sites on body
Since approximately 50% of body fat is located under skin, predictions can be made about total body fat

12. Skinfolds Advantages & Disadvantages Cost Availability Complexity
User/equipment error
Quality/quantity of information
Accuracy

13. Bioelectrical Impedance Analysis
A small, painless electrical current passes through body
Based on current difference between starting and ending points, percent fat can be estimated
Fat impedes/resists current more than fat-free mass
High impedance values will reflect higher fat mass

14. Bioelectrical Impedance Analysis
Advantages & Disadvantages
Cost
Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

15. Hydrostatic Weighing
Person weighed in regular environment, and under water
Based on difference, can eventually estimate body volume
From volume, one calculates body density
From body density, fat percentage calculated
Higher density = leaner subject (bone, muscle are denser than fat)

16. Hydrostatic Weighing Advantages & Disadvantages Cost Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

17. Air Displacement Similar to hydrostatic weighing
Device measures air displacement to determine body volume
From volume one can calculate body density
From body density, fat percentage is calculated

18. Air Displacement Advantages & Disadvantages Cost Availability
Complexity
User/equipment error
Quality/quantity of information
Accuracy

19. Dual Energy X-Ray Apsorptiometry (DEXA)
Low-radiation dose of dual-energy x-ray beams pass over body
Based on attenuation of x-ray, measures of fat, bone and soft lean tissue can be made
Based on these measures, fat mass can be calculated

20. DEXA Advantages & Disadvantages Cost Availability Complexity
User/equipment error
Quality/quantity of information
Accuracy

21. What is Average?
Body Fat Ranges for Standard Adults (NIH/WHO BMI Guidelines)
Percent Body Fat Norms for Men and Women (American Council on Exercise)