BMI stands for body mass index. According to the National Strength and Conditioning Association (NSCA), BMI is the preferred body composition assessment for obese individuals. The association states that the BMI classifications are as follows: less than 18.5 is considered underweight, 18.5 to 24.9 is normal, 25.0 to 29.9 is overweight and 30.0 to 39.9 is thought to be obese, while any BMI greater than 40 is considered extremely obese.
Step 1
Determine your weight in pounds. Write it down on paper. For example, if you weigh 250 pounds, list your weight as 250 lbs.
Step 2
Determine your height in inches. Write it down on paper. For example, if you are 6 feet, 1 inch, list your height as 73 inches.
Step 3
Square your height using a calculator. In other words, multiply your height by your height. For example, if your height is 73 inches, your equation looks like this: 73 x 73. Your height squared is 5,329.
Step 4
Divide your weight by your height squared. For example, if your weight is 250 lbs. and your height squared is 5,329, your equation looks like this: 250 / 5,329. Your answer is 0.0469131.
Step 5
Multiply the answer of your weight divided by your height squared by 703. For example, if your weight is 250 lbs. and your height is 73 inches, your equation looks like this: 0.0469131 x 703. The answer is your BMI. In this example, your BMI is 32.9.
Step 6
Compare your BMI to the chart given by the NSCA. Using the information given, with a BMI of 32.9, you would be classified as obese.
Tips and Warnings
- It is best to write down all your numbers, so you do not confuse them.
- The American Council on Exercise states that BMI should ideally be used in conjunction with other body composition assessments, because BMI does not discriminate between the overfat and the more muscular body type. In other words, a body consisting of higher muscle mass may receive an unreliable BMI score.
Things You'll Need
- Pen or pencil
- Paper
- Calculator
- NSCA BMI chart
References
- "Essentials of Strength Training and Conditioning"; National Strength and Conditioning Association; 2000
- American Council on Exercise: BMI Doesn't Distinguish, Why is it so Widely Used?
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