Ideal Body Weight (IBW) normally body weight is assumed to be in perportion of height, but this doesn't include the body frame size. Our Ideal Body Weight calculator uses wrist size to calculate body frame size and Ideal Body Weight is aptly calculated using body frame size and height.
Body Mass Idex (BMI) is the ratio of your weight to the square of your height. The number is proportional to your body shape. Generally, the number is small for thin people and large for fat people. People with a BMI 25 or greater are considered overweight, unless they have a very muscular body. The BMI does not consider the fat/muscle ratio, and a healthy, muscular individual with a low percentage of body fat may be classified obese using the BMI formula. This is a well-known deficiency of the BMI formula.If your BMI is 25 or greater, and your Waist-to-Height ratio is less than 0.5 and your Percent Body Fat is in the "athlete" or "fitness" category, you are probably muscular and not fat.
- Underweight BMI less than 18.5
- Normal weight BMI 18.5 to 24.9
- Overweight BMI 25 to 29.9
- Obese BMI 30 or greater
Waist To Height Ratio (WTHR) is determined by dividing the waist circumference by the height. Waist-to-Height ratios of 0.5 or greater are indicative of intra-abdominal fat for both men and women and are associated with a greater risk of cardiovascular disease. A study found that persons with a normal BMI but a large waist circumference, corresponding approximately to a Waist-to-Height ratio of 0.55, had a 20% higher mortality risk than persons with a normal waist size.
Percentage Body Fat (PBF) is calculated using the formulas developed by Hodgdon and Beckett at the Naval Health Research Center in 1984. The formulas require the measurements to be in centimeters with an accuracy of 0.5 cm. However, the form above has been adjusted to accept measurements in inches. Men and women require different methods for measuring because men accumulate fat mostly in the abdomen (the "apple" body shape or "beer belly"), while women accumulate fat in their abdomen and hips (the "pear" body shape). The equations take this into consideration.
The American Council on Exercise uses the following categories based on percentage of body fat:
| | |
Essential Fat | 10 - 12% | 2 - 4% |
Athletes | 14 - 20% | 6 - 13% |
Fitness | 21 - 24% | 14 - 17% |
Acceptable | 25 - 31% | 18 - 25% |
Obese | 32% or more | 26% or more |
Lean Body Mass (LBM) is mass of all body components excluding body FAT. This is derived by subtracting the calculated value of body fat from the total weight.
Waist To Hip Ratio (WTHR) is determined by dividing the waist circumference by the hip circumference. Waist-to-Hip ratios of 1.0 or greater are indicative of pear shape body for both men and women and are associated with a greater risk of cardiovascular disease. The bottom line is your waist should always be less than your hip.