What is BMI?
Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared.
BMI is used to categorize a person as underweight, normal weight, overweight, or obese. It is a useful population-level measure of healthy weight ranges.
BMI Categories
- 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
Limitations of BMI
While BMI is a useful screening tool, it has limitations. It does not directly measure body fat and may not accurately reflect health status for athletes, elderly individuals, or those with high muscle mass.
Always consult with a healthcare professional for a comprehensive health assessment.
Frequently Asked Questions
How is BMI calculated?
BMI is your weight in kilograms divided by your height in metres squared. Using imperial units, weight in pounds is divided by height in inches squared and multiplied by 703.
Is BMI accurate for athletes?
BMI does not distinguish muscle from body fat, so muscular athletes may be classified as overweight despite having a healthy body composition. Use it as a screening measure alongside other health and performance indicators.
What is considered a healthy BMI?
For most adults, a BMI from 18.5 to 24.9 is commonly classified as the healthy range. Age, pregnancy, ethnicity, muscle mass and medical history can affect how a result should be interpreted.
Optimize Your Training with Precision
Unlock the full potential of your workouts with our Heart Rate Zone Calculator at TrainerPlan. Discover a personalized training regime that adapts to your fitness goals
Sign up for free