Because a bathroom scale can't distinguish between body fat and muscle, it is important to look at additional factors to help complete an estimate of overall health and fitness. One of the easier and more helpful measurements to take is the circumference of the waist and hips. The ratio of these two numbers is an indicator of risk for lifestyle-related illnesses such as heart disease and diabetes.

Use a tape measure to measure the waist below the rib cage but above the belly button. Then measure the hips around the widest part of the butt. It might be helpful to take these measurements in front of a bathroom mirror to ensure that the tape measure remains level.