How to Figure Out My Lean Weight Manually
- 1). Weigh yourself on your scale. Record your body weight in pounds.
- 2). Measure your waist. Line your tape measure up with your navel all the way around your body. Record the measurement in inches.
- 3). Plug your measurements into the formula for females if you are female: (4.15 x waist measurement) - (0.082 x weight) - 76.76 / weight). This is your body fat percentage.
- 4). Plug your measurements into the formula for males if your are male: (4.15 x waist measurement) - (0.082 x weight) - 98.42 / weight). This is your body fat percentage.
- 5). Multiply your body-fat percentage by your weight. This is your body fat in pounds. Subtract your body fat in pounds from your total body weight. This number is your lean mass.
For example, if you weigh 150 pounds and you are a female with a 0.2 body fat percentage (20%), your equation would look like this:
(0.2 x 150) = 30 pounds of fat
(150 - 30) = 120 pounds of lean mass
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