Body Composition Weight Management: Overview

1. Body Composition & Weight Management: Overview PEP 418 University of Idaho

3. What is Body Composition? Body Composition is… The proportion of Fat and Fat-free Mass (muscle, bone, and water) in the body. Fat Mass: Essential and Non-essential Fats Fat-Free Mass: Muscle, Bone, Water, Tissues, etc. Body Composition is usually recorded as Percent (%) Body Fat.

4. How much is too much? Overweight is the total body weight over the recommended range for good health. Obesity is a more serious degree of overweight. These two classifications can be estimated using either height & weight formulas or body composition.

5. What is a Healthy Body Comp.?

6. So, what should I really be interested in? Body Composition measures are Far More Accurate than measures derived from height and weight alone. Therefore, Body Weight is Not As Important to know as Body Composition.

7. We are getting FATTER! Is there any surprise by the fact that obesity and overweight rates have skyrocketed over the past 50 years? Consider this: More time spent in sedentary work and leisure More driving Less PE in school and less exercise after high school Fast Food and Portion Sizes: “Supersize me Sucka!”

8. What does this mean? Obesity causes more than 400,000 premature deaths each year in the US. Obesity costs the US over $100 billion annually. If we continue on our current path, obesity will soon surpass smoking as the Leading Cause of Disability and Death among Americans!

9. Obesity and Risk of Disease Obese people have a significantly higher Mortality Rate than non-obese people. This is probably due to the fact that blood fat levels are higher, which can Impair Heart Function, and Lead to CVDs. Obesity is also linked to increased hypertension, impaired immune function, sleep and respiratory disorders, pregnancy complications, etc. And the big winner: obesity is a sure path to Type II Diabetes!

10. What about being skinny then? Having a body comp. that is Too Low (Lower Than “Essential”) can also lead to problems. Extra leanness is linked with a multitude of reproductive, circulatory, and immune system disorders. Muscle wasting and fatigue are other possible complications. For women, too low % body fat can contribute to Amenorrhea and Loss of Bone Mass.

11. To effectively control your Body Comp., you must know how to ASSESS it… Body Mass Index (BMI) Body Composition Tests Hydrostatic Weighing Skinfold Measurements Bioelectrical Impedance Analysis Body Fat Distribution Waist Circumference Waist-to-Hip Ratio

12. Body Mass Index Uses height and weight estimates to predict % body fat based upon population norms. Advantages Convenient Can test large groups easily. Disadvantages Does not provide % Body Fat. For average people it can be an OK indicator of body comp, AT BEST! For healthy, active people, especially those who lift weights, BMI can be extremely inaccurate!

13. Body Comp. Techniques Hydrostatic/Underwater Weighing Weigh someone outside of water, weigh them in water, then use an equation to estimate Body Density, then calculate body fat. Muscle is more dense than water, fat is less dense compared to water, i.e. “fat floats” Advantages Considered the Gold Standard for indirectly estimating % body fat (Error is ~ ± 3%). Disadvantages Difficult to test large groups efficiently. Equipment may be expensive and hard to come by. Experience is Critical (as a tester and a participant).

14. Body Comp. Techniques Skinfold measurements Use calipers to “pinch-n-pull” skin and subcutaneous fat away from muscle, record Fat Thickness in mm. Using different sites and equations, sum of all the measurements estimates Body Density, then % BF. Advantages More convenient, cheaper, and accessible than hydrostatic weighing. Can be fairly accurate when performed by an experienced tester (Error is ~ ± 6%). Disadvantages Tester must have a ton of experience to produce valid and reliable results.

15. Body Comp. Techniques Bioeletrical Impedance Analysis (BIA) A small-voltage electrical current is sent through part of the body. Fat-free Mass conducts the current well, Fat Mass impedes it. The longer it takes the electrical current to pass through your body, the fatter you are. Advantages Most convenient, and potentially cost-effective, body comp. technique. Very little tester experience is required. Fairly accurate under the right conditions (Error is ~ ± 3-5%). Disadvantages Too many assumptions! Appendige-specific Equipment (upper vs lower vs full body). Hydration Status and Body Proportions significantly affect results.

16. Body Comp. Techniques Other methods of body comp. assessment include: The BodPod: uses Air Displacement to estimate body density, then calculates % BF. DXA technique: uses X-ray Technology to estimate body comp. TOBEC: uses Magnetic Field to estimate body comp.

17. Waist Circumference Waist-to-Hip Ratio Both rely on “apple” and “pear” morphology stats in formulas that estimate risk associated with Fat Distribution. Scores higher than the recommended cut-offs May Be An Indicator That You Are Obese. Advantages Convenient, cheap, and easy to assess. Can test large groups quickly. Disadvantages Assumes a lot. Does not provide % Body Fat. Body Fat Distribution

18. How can I control my Body Composition? Good Nutrition, Regular Exercise, and Balanced Wellness are controllable factors AND THE KEY TO SUCCESS! It is important not to underestimate the role of nutrition in this equation! There is no spot reducing, no magic pills, no shortcuts, and no liposuction remedies that will reduce and/or keep body fat off in a safe and effective manner!