1. Body Composition
Chapter 4

2. Objectives
Define body composition and understand its relationship to assessment of recommended body weight.
Explain the difference between essential fat and storage fat.
Describe various techniques used to assess body composition.

3. Objectives
Be able to assess body composition using skinfold thickness and girth measurements.
Understand the importance of body mass index (BMI) and waist circumference in the assessment of risk for disease.

4. Objectives
Be able to determine recommended weight according to recommended percent body fat values and BMI.
Learn how to measure body composition.
Assess your risks for potential disease.

5. Introduction Body composition Recommended body weight
Fat component
Percent body fat
Nonfat component
Lean body mass
Recommended body weight
Assessment of body composition

6. Essential and Storage Fat
Total fat
Essential fat
Normal physiological function
Locations
Percent of total weight
Storage fat
Functions
Location of storage

7. Typical Body Composition of an Adult Man and Woman

8. Techniques to Assess Body Composition
Dual Energy X-ray Absorptiometry (DEXA)
Research and medical facilities
Measurements
SEE ± 1.8 percent

9. Techniques to Assess Body Composition
Hydrostatic weighing
Most common technique
Buoyancy of fat tissue
Drawbacks
SEE ± 0.5 percent

10. Techniques to Assess Body Composition
Air displacement
Bod Pod
Air displaced by person inside the chamber
Comparison to hydrostatic weighing
SEE ± 2.2 percent

11. Techniques to Assess Body Composition
Skinfold thickness
Anthropometric measurements
Relation of subcutaneous fat and total body fat
SEE ± 3.5 percent
Skinfold sites
Hydration and physical activity

12. Techniques to Assess Body Composition
Girth measurements
Limitations
SEE ± 4 percent
Measurement locations
Women: upper arm, hip, and wrist
Men: waist and wrist

13. Body Fat Assessment According to Girth Measurements

14. Techniques to Assess Body Composition
Bioelectrical impedance
Accuracy is questionable
10 percentage points
Measure of electrical resistance
Fat tissue is less efficient conductor
Factors that can affect results

15. Body Mass Index (BMI) Determine thinness and excessive fatness
Height and weight to estimate fat values
Calculations
Most widely used measure to determine obesity and overweight
Disease risk
Lowest risk range

16. Mortality Risk Versus Body Mass Index (BMI)

17. Body Mass Index (BMI) Compared with a BMI between 22-25:
BMI greater than 25
Mortality rates
Weakness of BMI
Location on body fat
Use with athletes

18. Disease Risk According to Body Mass Index (BMI)

19. Overweight & Obesity Trends in the U.S., 1960-2006

20. Waist Circumference Storage of fat affects disease risk
Android obesity
Apple shape
Risks
Fat around organs
Gynoid obesity
Pear shape
Waist circumference measurements

21. Disease Risk from WC and BMI

22. Determining Recommended Body Weight
Mortality
Obesity vs. underweight
Essential fat
Lean tissue decreases with age
Extra fat percentage for each decade of life
Computing recommended body weight

23. Body Composition Classifications According to Percent Body Fat

24. Importance of Regular Body Composition Assessment
Fat gain
Weight gain per year
Lean tissue lost per year
Body composition reassessment

25. Visceral Fat Compared to SBC or RTP Fat for Disease Risk

26. Real Life Stories

27. Real Life Stories Critical Thinking Questions
1. Can you identify what got Camille started on her weight-loss program? Was the starting point self- or environmentally determined? Discuss the pros or cons that got her going on her weight-loss program. How was the end point of the weight loss determined? List the benefits of her long-term approach to weight loss.
2. What weight-loss programs are likely to end up being just another “yo-yo diet”? Have you had any experiences with some of these methods; and if so, what were the results? What strategies are more likely to lead to permanent and sustainable weight loss?
3. Discuss the roles of aerobic exercise and strength training on weight management. Do you think strength training is a good idea for those who are trying to lose weight? Is it as important for women as for men?