BMI Calculator for Bodybuilders

Many doctors use BMI to determine your weight and health risk. BMI is calculated by dividing a person’s weight in kilograms by their height in meters. 18.5 to 24.9 is healthy, 25 to 29.9 is overweight, and 30 or more is obese. While BMI is generally accurate, it frequently misclassifies muscle-bound bodybuilders as overweight or obese. Bodybuilders and other athletes should use alternate approaches to assess their health.

When to Use BMI


For a vast percentage of people, BMI reliably identifies overweight or obesity and elevated disease risk. It’s easy to measure because the formula doesn’t alter for age or gender. When calculating BMI for children and adolescents, the findings are interpreted differently to account for age and gender, as girls naturally gain weight as they enter puberty.

A medical checkup should reveal whether your bodybuilding routine skews your BMI. Because BMI is a fixed number, bodybuilders should not use it as a measure of obesity.

How to Calculate Bodybuilder’s BMI

With little muscular mass but a lot of fat in the middle, BMI can overstate body fat in bodybuilders and underestimate it in those of average weight. Waist circumference may be a better indication of health for both groups. A waist circumference of 40 inches for men and 35 inches for women may indicate excessive visceral (intra-abdominal) fat.

Intense metabolic activity of this type of fat increases the risk of chronic diseases like heart disease and Type 2 diabetes. Your waist may be greater than expected if you have a thicker midsection from abdominal and back muscles, even if you don’t have much visceral body fat.

So, if you’re an athlete or a bodybuilder, how do you figure out your body fat percentage? Methods for obtaining results from an examination of overall body composition are available. Skin thickness measurement, hydrodensitometry, and bioelectric impedance are the most frequent fat calculation methods.


A complex weighing of a person below the water level is known as hydrodensitometry. Because this is a difficult operation that necessitates specialized conditions and equipment, most specialists rely on basic caliper measurements of skin thickness.


Body fat caliper is the most widely used method of calculating body fat. It works by taking measurements of the thickness of the skin on various regions of the body and then entering the results into a formula. Finding out how much fat you have in your body is the end outcome.

Bioelectric impedance

A typical approach for assessing body fat percentage is bioelectric impedance. It is a body composition measurement based on the rate at which electric current travels through the body. Adipose tissue generates higher resistance (impedance) than muscle mass, slowing the current’s movement. This approach calculates total body weight, body fat percentage and %, muscle mass, water, and even bone tissue. Although the amount of hydration and other circumstances may have a minor impact on its outcomes, it nevertheless offers reasonably accurate results. Body fat scales are available in specialty stores and can also be used at home.

Skinfold Test Use

Rather than relying on BMI, perform the skinfold test to determine your body fat percentage. Your trainer or doctor should be able to help you with this. The skinfold method involves pinching and measuring your skin at several spots on your body, commonly your triceps, abdomen, and shoulder blades. These numbers are then entered into a formula to calculate body fat.

Other Options

If you’re serious about competing, you may want to invest in more precise body fat assessment tools. Hydrostatic weighing is one of the most precise. This method involves being submerged in water and weighed while underwater. To determine body fat, your submerged weight must be added to your land weight. It’s easy to find a BIA facility. This approach uses an electrical current to measure resistance. The faster the current moves through your body, the more muscle mass you have compared to fat.

What does the resulting BMI value mean?

BMI calculates your weight and potential health risks. The table below provides conventional categories for adults based on BMI. Comparing your BMI to the table below will reveal your body composition.

below 18,5underweightmedium
18,5 – 24,9healthy weightlow
25,0 – 29,9overweightmedium
30,0 and moreobesityhigh

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