Step 2: Assess Your Fitness Level
Body Composition
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Body weight alone is not a good indicator of overall health and fitness. Body composition is a better indicator of health and fitness.
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Body composition is the ratio between fat mass (body fat) and lean body mass (non-fat components).
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Percent body fat is the fat mass in the body based on total body weight. Both essential fat and storage fat constitute total body fat.
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Not enough body fat is unhealthy. Essential body fat protects delicate organs, provides insulation, and is an important element for nerve conduction. Essential body fat is about 3% for men and 12% for women. However, research suggests that for best health and fitness men's body fat should range between 10-18%, and the women's range is 15-23%.
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Being over-fat, or having a high ratio of body fat to lean body mass, is associated with a higher risk for chronic disease.
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Muscle weighs more than fat. Athletes and other highly muscled individuals are heavier than average, but not necessarily unhealthy. Body weight alone does not identify body fat values, or accurately determine a negative effect on health.
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Weight and height charts are notoriously inaccurate as an indicator of health and wellness.
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Spot reduction is a fallacy. One can not reduce fat stored on a specific point of the body by engaging in an exercise targeting that body part. Continuous, low intensity, multi-joint activities (e.g. running, walking, and swimming) will reduce fat stores throughout the body.
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Changes in one's body composition measurements will take at least two weeks. Quick losses of body weight in most cases are from loss of water and lean body mass. Slow changes in either weight loss or gain are more likely to be maintained.
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One pound of body fat is equal to 3500 calories. Or about thirty-five miles of walking.
Bioelectrical Impedance Analysis
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Bioelectrical impedance analysis is a simple assessment used in our fitness center to determine the body composition of students.
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The BIA machine is checked out by students at the front desk.
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A weak electrical current is run through the body to estimate lean body mass and body fat. Lean tissue is a better conductor of electricity than body fat. The speed that the current travels through the body is used in a calculation to determine the percentage of body fat.
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Research shows that bioelectrical impedance analysis is not as accurate as hydrostatic weighing, air displacement, and skin fold thickness assessments. However, those methods require expensive equipment, practice to administer correctly, and a degree of privacy. Students can easily administer the bioelectric impedance analysis technique to themselves.
Pre-requisite:
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Do not use the Bioelectrical Impedance Analysis machine if you use a pacemaker or other electrical implants. The BIA machine may damage these devices.
Equipment:
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Bioelectrical Impedance Analysis Machine (Available at Fitness Center counter.)
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Athletic shorts and t-shirt. Sweats or bulky clothing will affect the outcome of the test.
Protocol:
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Do not eat a heavy meal or smoke within 3 hours of this assessment.
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Avoid vigorous activity 24 hours prior to test.
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Take this assessment before working out. Dehydration will affect the outcome of this assessment.
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For best accuracy, this assessment should be repeated for 3-5 consecutive days, using the average of these scores.
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Record the final score and calculate your recommend body weight by using the following formula.
Recommended Body Weight
Using Body Fat Percentage
To calculate your optimal body weight:
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Determine your pounds of body weight in fat (FW) by multiplying your body weight by your current percent of fat expressed in decimal form.
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FW = (BW) (%BF)
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Calculate your lean body mass (LBM) by subtracting your weight in fat (FW) from your total body weight. Lean body mass is the nonfat component of the body.
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LBM + BW - FW
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Select your desired body fat percentage (DFP) based on your health of fitness goals by using standards given in the following chart.
MEN
| Age |
Excellent |
Good |
Moderate |
Overfat |
Obese |
|---|---|---|---|---|---|
| =19 |
12 |
12.1 -17.0 |
17.1 - 22.0 |
22.1 - 27.0 |
=27.1 |
| 20 - 29 |
13.0 |
13.1 - 18.0 |
18.1 - 23.0 |
23.1 - 28.0 |
=28.1 |
| 30 - 39 |
14.0 |
14.1 - 19.0 |
19.1 - 24.0 |
24.1 - 29.0 |
=29.1 |
| 40 - 49 |
15.0 |
15.1 - 20.0 |
20.1 - 25.0 |
25.1 - 30.0 |
=30.1 |
| >=50 |
16.0 |
16.1 - 21.0 |
21.1 - 26.0 |
26.1 - 31.0 |
=31.1 |
WOMEN
| Age |
Excellent |
Good |
Moderate |
Overfat |
Obese |
|---|---|---|---|---|---|
| =19 |
17.0 |
17.1 - 22.0 |
22.1 - 27.0 |
27.1 - 32.0 |
=32.1 |
| 20 -29 |
18.0 |
18.1 - 23.0 |
23.1 - 28.0 |
28.1 - 33.0 |
=33.1 |
| 30 - 39 |
19.0 |
19.1 - 24.0 |
24.1 - 29.0 |
29.1 - 34.0 |
=34.1 |
| 40 - 49 |
20.0 |
20.1 - 25.0 |
25.1 - 30.0 |
30.1 - 35.0 |
=35.1 |
| =50 |
21.0 |
21.1 - 26.0 |
26.1 - 31.0 |
31.1 - 36.0 |
=36.1 |
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Compute your recommended body weight (RBW), or goal body weight, by using this final calculation.
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RBW = LBM ÷ (1 - DFP)
Example:
Sex: Male
Age: 23
Body Weight: 185
Percent of body fat: 21.9% (.219)
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Body Fat Weight = BW X %Body Fat
Body Fat Weight = 185 X .219 = 40.515 lbs. -
LBM = BW - Body Fat Weight
LBM = 185 - 40.515 = 144.485 -
Desired Fat Percentage: 13%
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Recommended body weight = Lean Body Mass ÷ (1.0 - DFP)
RBW = 144.485 ÷ (1.0 - .13)
RBW + 144.485 ÷ (.87) = 166.07
Work Sheet
Body Fat Weight _________ = BW _________ X % Body Fat _________
Lean Body Mass _________ = BW __________- BFW __________
RBW _________ = LBM _________÷ (1.0 - DFP_________ )
Recommended body weight (RBW), or goal body weight, is based on your current lean body mass (LBM). Diet and exercise have an effect on lean body mass. Lean Body Mass increases with resistance training. Therefore, the recommended body weight will also increase. Fitness experts suggest that body fat percentage (BFP) assessment and recommended body weight (RBW) estimation should be done about once every month.
Hoeger, W A., and Hoeger, S. A. Lifetime Physical Fitness and Wellness - A Personalized Program (Englewood, CO: Morton Publishing Company, 1998), 17 - 21.