BMI (Body Mass Index) is a measure that uses your height and weight to estimate how much body fat you have. It's calculated by dividing your weight in kilograms by your height in meters squared. It's commonly used to classify underweight, normal weight, overweight, and obesity in adults.
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform its most basic (basal) life-sustaining functions. These functions include breathing, circulation, cell production, nutrient processing, protein synthesis, and ion transport. Essentially, BMR represents the amount of energy (calories) required to maintain your body's physiological processes at rest.
BFP (Body Fat Percentage) is the percentage of your body weight that is fat. It's a more accurate measure of fitness than BMI because it differentiates between lean mass (muscle, bone, water, etc.) and fat mass.
The American Council on Exercise Body Fat Categorization
| Description | Women | Men |
|---|---|---|
| Essential fat | 10-13% | 2-5% |
| Athletes | 14-20% | 6-13% |
| Fitness | 21-24% | 14-17% |
| Average | 25-31% | 18-24% |
| Obese | 32+% | 25+% |
| Age | Women | Men |
|---|---|---|
| 20 | 17.7% | 8.5% |
| 25 | 18.4% | 10.5% |
| 30 | 19.3% | 12.7% |
| 35 | 21.5% | 13.7% |
| 40 | 22.2% | 15.3% |
| 45 | 22.9% | 16.4% |
| 50 | 25.2% | 18.9% |
| 55 | 26.3% | 20.9% |