IF YOU WANT TO KNOW WHAT WORKS FOR CALCULATING BODY FAT PERCENTAGE AND WHAT DOESN’T, THEN YOU WANT TO READ THIS ARTICLE.
in this article, I want to share what I’ve learned, including…
What body fat percentage is.
The pros and cons of popular ways of calculating body fat percentage.
How to determine your body fat percentage with a fair amount of accuracy.
What is more helpful to track than body fat percentage.
Let’s get started.
What Is Body Fat Percentage?
Your body fat percentage is the percentage of your weight that is fat. For example, if you weigh 150 pounds and have 15 pounds of fat, your body fat percentage is 10% (15 / 150).
Your body fat changes when you gain or lose fat, of course, but it also changes when you gain or lose muscle.
If you used proper diet and workouts to increase your weight from 150 to 170 pounds, for example, and gained just 5 more pounds of fat, your new body fat percentage would be about 12% (20 / 170).
If you then stopped lifting for a year and lost, let’s say, 10 pounds of muscle but no fat, your body fat percentage would still be about 12% (20 / 160). So, your body fat percentage ebbs and flows as you change your body composition.
Why Body Fat Percentage Is More Important Than BMI
Many people mix up body fat percentage and BMI, but they’re completely different.
BMI stands for “body mass index” and it’s a numeric expression of the relationship between your height and weight.
You calculate your BMI by dividing your weight in kilograms by your height in meters squared.
For example, here’s my BMI is:
184 (pounds) x 0.45 = 82.8 (kilograms)
74 (inches) x 0.025 = 1.85 (meters)
1.85 x 1.85 = 3.4225
82.8 / 3.4225 = 24.2 (BMI)
And here’s how BMI values are correlated with body weight status:
Underweight = <18.5
Normal weight = 18.5–24.9
Overweight = 25–29.9
Obesity = BMI of 30 or greater
As you can see, according to the BMI measurement, I was borderline overweight.
Well, that’s the problem with BMI: it’s useful for analyzing broad populations but not so useful for assessing individual fitness.
Body fat percentage is much better for this purpose.
What’s a Healthy Body Fat Percentage for Men and Women?
As much as it’s despised, body fat is much more than a layer of ugly, oily flesh. It plays many vital roles in the body, including protecting organs from damage, maintaining body temperature, producing hormones and other chemicals, and much more. That’s why there is a limit to how lean you can get before your health declines. What is that limit, though? Well, here’s how various body fat ranges are classified for both men and women:
Essential Body Fat
2 – 4%
9 – 11%
6 – 13%
14 – 20%
14 – 17%
21 – 24%
18 – 25%
25 – 31%
Unless you’re a competitive bodybuilder and know exactly what you’re doing, don’t try to reach the Essential Body Fat range.
The lower end of the athletic range is the “shredded” look so many people are after these days.
Anyone can get here with proper dieting and exercise, but it’s very tough to maintain for long periods of time.
Maintenance of this look requires strict control of caloric intake, which can be particularly hard if you’re fighting against your body’s natural set point.
The “fit” range looks healthy and athletic but lacks the definition and razzle-dazzle of lower body fat levels.
I generally recommend that people don’t exceed the fit range. It slows down muscle growth and makes subsequent efforts to get lean long and grueling.
The middle range of normal is where you begin to look decidedly “overweight,” and health problems can begin as you move into the obese range.
If you want to feel good and reduce your risk of chronic disease, you don’t want to get this fat.
How to Calculate Your Body Fat Percentage
There are quite a few ways of calculating your body fat percentage and you can get quite a few different results.
In my case, the multiple-point caliper test said 11%, but the handheld device (which we’ll talk about soon) said 8%, and a different single-point caliper said 6%.
Body Composition Scales & Handheld Devices
The simplest way to measure your body fat percentage is with a scale or handheld device. These instruments use a method called bioelectrical impedance analysis (BIA), which involves measuring your body’s resistance to a light electrical current.
Muscle conducts electricity well because it’s over 70% water and fat doesn’t because it holds much less water. Thus, the more resistant the body is to an electrical current, the fatter it must be. That sounds reasonable enough but there are serious problems with BIA…
Electricity will take the path of least resistance.
As the current passes through your body, it will avoid fat stores for tissues that are easier to traverse. (Internal tissues will be chosen over subcutaneous fat, for example.) Making matters worse is the fact that two-electrode devices (like most scales and handhelds) skip entire portions of your body. Foot-to-foot scales miss your entire torso and hand-to-hand devices miss the lower half of your body.
As you can imagine, this corrupts the results. Another problem with BIA is it uses mathematical equations to turn raw readings into body fat percentages and these equations can be fundamentally flawed. You see, when a company develops a BIA device, they calibrate it using another imperfect method of measuring body fatness like hydrostatic weighing.
There are several steps involved:
Measuring the body fat of a large group of people with the “control” method.
Measuring them again with the BIA device.
Comparing the readings.
Developing an equation to predict BIA results based on height, weight, gender, and other variables.
This could work if the control method’s readings were accurate, but they’re often not.
That is, many companies are calibrating their BIA devices to conform to incorrect calculations of body fat percentage.
Hyrdrostatic weighing is most frequently used for BIA benchmarking, and studies show it can be off by as much as 6% for various reasons relating to ethnicity, body weight, hydration status, and more. If 6% off doesn’t sound too bad to you, realize that when I’m talking error rates in this article, I’m talking in absolute terms, not relative. In other words, someone at 10% body fat may register at 16% with hydrostatic weighing.
Body conditions can dramatically influence readings.