Body fat is typically expressed as a percentage of your total body weight, as opposed to the actual amount of fat in your body. You will typically experience a decrease in your body fat percentage as you follow a fitness program. You can test your body fat percentage from your weight and some other body measurements. This will allow you to record your progress as you gain muscle and lose fat.
Step 1
Measure the circumference of your waist inches at your navel. Weigh yourself in pounds. Take these measurements when you first wake up so that your water weight will be at its lowest level.
Step 2
Take additional measurements if you are female. Measure the circumference of your forearm and hips at their widest points. Measure the circumference of your wrist at its narrowest point. All of these measurements should be recorded in inches.
Step 3
If you are male, derive your lean weight with this formula: (weight x 1.082) -- (waist x 4.15) + 94.42. For example, if you have a 36-inch waist and weigh 185 lbs., your lean weight is (185 x 1.082) -- (36 x 4.15) + 94.42 = 145 lbs.
Step 4
If you are female, calculate your lean weight using this formula: (weight x 0.732) - (waist x 0.157) + (forearm x 0.434) - (hips x 0.249) + (wrist / 3.14) + 8.987. For example, you have a 30-inch waist and weigh 125 lbs. Your forearm measures 10 inches, your hips measure 38 inches and your wrist measures 7 inches. Your lean weight is (125 x 0.732) - (30 x 0.157) + (10 x 0.434) - (38 x 0.249) + (7 / 3.14) + 8.987 = 93 lbs.
Step 5
Compute your body fat using this formula: (total weight - lean weight) x 100 / (total weight). For example, you weigh 185 lbs. and have a lean weight of 109 lbs. Your body fat percentage is (185 - 145) x 100 / 185 = 21.6 percent.
Things You'll Need
- Tape measure
- Scale
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