The pinch test technique is one of the most popular ways to estimate body composition. Inexpensive, accurate and easy to administer with a special caliper, the test determines a person's level of body fat. This figure is directly related to health outcomes, including the risk of developing obesity, hypertension, stroke, heart disease and type 2 diabetes.
Locate the three skin fold sites to be pinched with the caliper. Measurement sites for men include the chest skin fold, located between the nipple and the arm pit, the thigh skin fold in the middle of the front upper thigh and the abdomen, about 1 inch away from the navel. For women, measure the triceps, thigh and suprallium, located at the top of the hip bone on the natural fold.
Grab each skin fold using your thumb and index finger. Place the caliper pads about one-quarter inch from the skin's base. The triceps and thighs should be measured with the caliper in a vertical position perpendicular to the skin. When measuring the suprallium skin fold, hold the caliper in the natural direction of the line. Squeeze the caliper until the trigger sets.
Release the caliper's triggers and record the reading. Repeat the above steps once more to ensure the accuracy of your readings. If your measurements vary by less than 1 mm, the readings are accurate. If they differ by more than 1 mm, repeat the measurements until you achieve a more accurate reading, taking care to measure in the same spot each time.
Calculating Body Density For men, the body density formula is as follows: Body Density = 1.10938 – (0.0008267 x the sum of the chest, thigh and abdomen skin folds in mm) + (0.0000016 x square of the sum of chest, abdomen and thigh) - (0.0002574 x age). For women, the body density formula is as follows: Body Density = 1.0994921 - (0.0009929 x sum of thigh, triceps and suprailiac skin folds) + (0.0000023 x square of the sum of thigh, triceps and suprailiac skin folds) - (0.0001392 x age in years).
To calculate body fat percentage, divide 495 by the body density, then subtract 450 and multiply by 100 (Kasch).
Interpret the results of your calculations. A fit man may have a body fat percentage between 14 and 17 percent. 18 to 24 percent body fat is acceptable for men, but a percentage over 25 percent indicates obesity. For women, a body fat percentage between 21 and 24 percent indicates fitness, but a percentage between 25 and 31 percent is acceptable. A percentage over 32 percent is a sign of obesity (Ace Fitness).
References
Writer Bio
Poppy Carpenter graduated from the University of Missouri School of Journalism. In addition to teaching journalism to junior high students, she also covers health and fitness for "PUSH Monthly" and Angie's List.
