How It Works
The Bod Pod is an egg shaped device that measures body volume and body weight to determine body density and body fat. First, you step on an electronic scale outside of the device which measures your weight. Then, you measure the air pressure of the Bod Pod without you in it. Next, step into the chamber and let the machine measure the air pressure with you in it.
These values will give you the volume of the empty Bod Pod and the volume of the pod with you inside. Subtract these two numbers and you’ve got your body volume. Divide your weight by your volume and you’ve got your density. The software uses density to estimate body fat.
We tried a Bod Pod and it only took a few minutes to complete two testing trials. The results are printed immediately and you also get your resting metabolic rate (RMR) and total energy expenditure estimates (TEE). Recent research, such as this 2003 European Clinical Journal of Nutrition study and this 2002 American Journal of Clinical Nutrition study shows that the Bod Pod is safe and accurate for body composition analysis.
“BodPod is very accurate when compared with HW,” says Weil. “Depending on the population measured, the error can be as low as 1-2 percent.”
Since the procedure was so carefree, it’s hard to point to any negative aspect. There are certain things you must do in order for the rest to work properly.
“The Bod Pod is very sensitive to baggy clothing so you have to wear clothing that is form fitting and doesn’t have cotton in it because cotton traps air and the air compresses differently,” says Christopher Dunbar, PhD, MPH, CCEP, RCEP, FACSM.
“You also have to measure lung volume. Some people use the Bod Pod and they don’t do the lung volume measurement they just estimate lung volume from a person’s height, weight, gender and so on. There you lose some accuracy.”