how do i calculate body fat?

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1. For Women: Before you use the formulas, there are five measurements that are required (not fair, I know): Measurement 1: Bodyweight. Measurement 2: Wrist Circumference (measured at the widest point). Measurement 3: Waist Circumference (measured at your umbilicus). Measurement 4: Hip Circumference (measured at the widest point). Measurement 5: Forearm Circumference (measured at the widest point). Procedure: 1) Multiply your bodyweight by 0.732. à Bodyweight x .0732 = Result 1. 2) Add the result above to 8.987. à Result 1 + 8.987= Result 2. 3) Divide your wrist circumference by 3.14. à Wrist divided by 3.14 = Result 3. 4) Multiply your waist measurement by 0.157. à Waist x 0.157 = Result 4. 5) Multiply your hip measurement by 0.249. à Hip x 0.249 = Result 5. 6) Multiply your forearm measurement by 0.434. à Forearm x 0.434 = Result 6. 7) Add results 2 & 3. à Result 2 + Result 3 = Result 7. 8) Subtract Result 4 from Result 7. à Result 7 - Result 4 = Result 8. 9) Subtract Result 5 from Result 8. à Result 8 - Result 5 = Result 9. 10) Add Result 6 and Result 9. The result is your lean body mass (your fat free weight) à Result 6 + Result 9 = Lean Body Mass. 11) Subtract your lean body mass from your bodyweight. Once you get the result, multiply that number by 100. Once you get this result, divide it by your bodyweight. à ((Bodyweight-Lean Body Mass) x 100) divided by your bodyweight. Example: A woman that weighs 125, and has a wrist measurement of 6.0, a waist measurement of 24, a hip measurement of 38, and a forearm measurement of 9.5 would calculate her body fat percentage in the following manner. Step 1: 125 x 0.732=91.5. Step 2: 91.5 + 8.987=100.487. Step 3: 6 divided by 3.14=1.91. Step 4: 24 x 0.157=3.768. Step 5: 38 x 0.249=9.462. Step 6: 9.5 x 0.434=4.123. Step 7: 100.487+1.91=102.397. Step 8: 102.397-3.768=98.629. Step 9: 98.629-9.462=89.167. Step 10: 4.123+89.167=93.29 (Lean Body Weight: Fat Free Weight). Step 11: ((125-93.29) x 100) divided by 125 = (31.37 x 100) divided by 125 = 3171 divided by 125= 25.368 (Body Fat Percentage). --- Notes: The formulas above are just approximations. The goal here is to have a point of reference from which to work. I recommend that you measure your body fat every three weeks. If you see a pattern where you see yourself gaining muscle and losing fat, then you know your program is right on track. If not, examine which part of your program is not optimal. Assuming that you are following an effective training routine, look at the things that could be going wrong such as you are not getting enough rest at night or more likely you are not following your nutrition plan to the letter. Since I like to measure my progress, and that of others, in the shortest amount of time possible, I created a computer program that once you enter the required inputs, it calculates in a microsecond your lean body mass, fat mass, and body fat percentage. It sure beats using the calculator, the pen or pencil and the piece of paper. Have fun!
2. wow, that person had a long explanation--- just search yahoo for a BMI calculator