How do I Calculate My BMI and Body Fat?
BMI Vs. Body Fat Percentage
Body Mass Index (BMI) and Body Fat percentage are two totally different measurements that are often mistakenly considered interchangeable. Body Mass Index and Body Fat Percentage are definitely different.
What is Body Mass Index (BMI)?
Body Mass Index is a measure of body fat based on your height and weight. Physicians widely consider BMI measurements as a simple way to determine if a person is healthy or unhealthy, underweight or overweight. It is important to note, that your BMI score is not a recommendation of what you should weigh…it’s more a general guideline.
How to Calculate your BMI
BMI = Your weight (in pounds) x 703
Your height in inches squared
Let’s look at an example of a person that is 5’7 weighing 150 pounds
BMI = 150 x 703 BMI = 105,450 BMI= 23.49
67 x 67 4,490
You can use the IIFYM BMI calculator to get your BMI.
Your BMI Range
According to the American Council on Exercise (ACE), there are five different ranges or body fat categories.
Keep in mind these categories are based on body fat norms and may not be a good indicator of your specific fitness level. ACE contends that, “a person’s overall health and lifestyle choices should be taken into account before making a decision about whether their percent body fat is acceptable or unacceptable.”
18.5 or below is considered underweight
18.5 to 24.9 is considered normal
25.0 to 29.9 is considered overweight
30 or above is considered obese
What about Body Fat Percentage?
Body Mass Index uses your weight in the formula but unfortunately it doesn’t take into account if that weight comes from fat or lean muscle tissue. Athletes who carry an abundance of lean muscle tissue may seem rather heavy for their frame or size but that’s because muscle weighs more than fat. These particular individuals may have a rather high BMI, but not have a great deal of fat. This is where Body Fat percentage takes over. Body fat percentage is the percentage of your body that consists of fat.
Women’s Body Fat Percentage
For females: a body fat percentage of:
10-12% is considered essential fat
14-20% is considered athletic
21-24% is considered fit
25-31% is considered acceptable
32% or more is considered obese
Men’s Body Fat Percentage
For males: a body fat percentage of:
2-4% is considered essential fat
6-13% is considered athletic
14-17% is considered fit
18-25% is considered acceptable
25% or higher is considered obese
Follow these guidelines for calculating the most accurate body fat percentage.
When to Take Measurements
To get the most accurate result, take measurements first thing in the morning. Your weight can fluctuate throughout the day so it’s wise to get your numbers before you’ve had anything to eat or drink.
What to Use
Once you’ve weighed yourself, you’ll need to take body measurements. Use a soft, flexible (cloth or fiberglass) tape measure. Don’t use an elastic tape measure.
How to Take Your Measurements
When you measure the circumference of each body part, the tape should feel firm enough against your skin so that it stays in place but not so tight that it causes an indentation.
You can use English or metric units. The measurements required for men and women are slightly different. Women require a bit more data.
Men
Current weight. Use a digital scale if possible.
Waist circumference. Take the measurement at the largest part of your belly, usually right at the level of your belly button. Make sure that the tape measure stays level to the floor. Don’t hold your breath or suck in to get the measurement.
Women
Current weight. Use a digital scale if possible.
Waist circumference. Take the measurement at the largest part of your belly, usually right at the level of your belly button. Make sure that the tape measure stays level to the floor. Don’t hold your breath or suck in to get the measurement.
Wrist circumference. Measure around the smallest part of your wrist. You may need a partner to help with this measurement as it’s hard to measure one-handed.
Hip circumference. Measure around the largest part of your hips, usually at the posterior extension of the gluteals (the place where your butt extends back).
Forearm circumference. Measure around at the widest part of your arm below your elbow. It’s easiest to have a partner get this measurement. Keep your arm relaxed during the measurement and let it hang alongside your body (don’t bend or flex the arm while measuring).
Once you’ve gathered your numbers, input the data to calculate your body fat percentage.
Body Fat Calculator
Why Measure Body Fat Percentage?
Whether you liked your result or not, you may wonder why body fat percentage matters. if your goal is weight loss, you might be tempted to use a scale for feedback on your progress. But body fat percentage tells you much more than the scale does.
When you’re trying to slim down, boost your health, or increase your level of fitness, fat loss should be your goal, rather than simple weight loss. You want to keep the lean mass, or fat-free mass, that your body needs. This includes bone, blood, connective tissue, organs, and muscle.
Muscle loss sometimes occurs when you are losing weight, but it’s not the kind of weight loss you’re looking for. You want to maintain muscle mass because it helps your body function and perform more efficiently, boosts your metabolism, and gives your frame a lean, tight appearance.
By measuring changes in body fat percentage, you can tell how well your fitness or weight loss program is helping you to lose fat while maintaining fat-free mass.
