Weighing in on Body Fat
How Much Is Right for Me?
Interest in the measurement of body fat has grown tremendously during the last 20 years, largely because of its relationship to both health and athletic performance. Scientific data have linked obesity (an excessive accumulation of fat) with coronary heart disease, several types of cancer, stroke, diabetes, osteoarthritis, high blood cholesterol and high blood pressure. How do I know if my body fat poses a risk for my health?
BMI/Height & Weight Tables
BMI. Body Mass Index (BMI) is often used to screen for weight categories that may lead to health problems.
Calculated using your height and body weight, BMI is a very rough estimate of your overweight status and should be viewed as such. Although it is easily measured, it is not an accurate way of determining fatness or what you should weigh because it does not consider whether your composition of body weight is fat or muscle.
Height & Weight Tables. Height and weight tables are also a very poor method for determining overweight status. Similar to BMI, these tables do not consider body composition and only provide weight ranges recommended for various heights.
Using improper methods or public ideals can be a dangerous practice for determining a target body weight. It is recommended that concerned individuals consider measurement of body composition as an alternative to body weight. Using body composition, you can determine what percent of your total weight is fat.
TargetWeight
Target weight is calculated as lean body weight (muscle & bone) plus the desired percentage of fat.
Target weight is the weight an individual is aiming to attain.
If you know your body fat, determine what percent is good for you using the standards above.
Then calculate your target weight using this formula:
Current weight x current % fat = fat weight
Current weight – fat weight = lean weight
Lean weight / (100% – desired %) = target weight
Waist to Hip Ratio (WHR)
Data show that it may make a difference where the excess fat is deposited, with respect to medical complications. Obese people most vulnerable to disease tend to have more fat deposited in abdominal areas rather than hips and thighs. In other words, certain health risks may be greater for those with much of their body fat in the trunk and abdominal areas. This is called android obesity (or apple‐shaped) in comparison to gynoid obesity (or pear‐shaped, characterized by deposition of fat in the hips and thighs).
The ratio of waist and hip circumferences (WHR) is a simple and convenient method of determining apple or pear‐shaped bodies (and obesity type present). Apples have a WHR > 0.80; pears have a WHR < 0.80.
How to determine your WHR:
- Measure your waist (directly on the skin) to the nearest quarter inch;
- Measure your hips around the buttocks. (Take several measurements at various levels and use the largest one); and
- Divide the waist measurement by the hip measurement (see below).
Lindsay, A. & Velasquez, S.
2008,
Weighing in on Fat: Using a Pedometer, A Guide to Help Step it Up
,
Extension | University of Nevada, Reno, FS-08-49.