Knowing your body composition is important because it can tell you a lot about your health. Body composition is how much of your body is fat and how much is not. It can be divided into fat mass (fm) and lean body mass (lbm). Lean body mass is how much of your body is muscle, bone, organs and everything else that is not fat. Why is this important? Well high percentages of body fat are associated with diabetes melitus, metabolic syndrome and cardiovascular disease. Also, research shows the correlation between body composition and all-cause mortality.
A study by Lee found “linear positive association between predicted fat mass and mortality from cardiovascular disease and cancer”. (Lee et al., 2018) We also know that low levels of lean mass are associated with sarcopenia (the natural muscle loss that occurs as we age), osteopenia (beginning stages of osteoporosis and the loss and weakening of bones) and osteoporosis (weak and porous bone more likely to fracture).
With this information I just want to share different methods of measuring your body composition. Let’s start with the ones you are most likely to come across.
Calipers: One of the most common measures of body composition. A personal trainer or trained professional will use a set of calipers to pinch folds of skin. Those numbers will be entered into a formula to calculate the percentage of body fat.
Pros: Easy to administer, low standard error if done correctly, low cost
Cons: Generally, can’t do it on yourself. Need a trained professional, can be invasive.
Bio-electric impedance (BIA): Another one of the most common measures of body composition. You hold a device and it shoots a small current through your body and determines the percentage of body fat by how much the signal was impeded.
Pros: Easy to administer, low cost
Cons: Can have a wide standard error (4.6 – 6.4 %), can be dependent on a multitude of factors like hydration and points of impedance. Cannot be used with a pace maker.
Composition Myography : Kind of like a combination of BIA and calipers. It uses a current and several sites to determine the percentage of body fat and also measures muscle quality.
Pros: Cheap and easy to administer, low standard error, gives your body composition and muscle quality.
Cons: Moderately priced equipment, really only one company that does this
There are several other methods that may not be as easily obtainable, those are: Dual-Energy X-Ray Absorptiometry (DXA), Hydrostatic Weighing and Air Displacement Plethysmography. I do not go into too much detail on these methods as they require equipment not easily attainable and are much more costly than the other methods. DXA and Hydrostatic weighing are the gold standard for body composition and can probably be done at a local university.
If you have access to a professional who can do calipers on you, feel free to use my calculator.
For those of you who have access to nothing but a measuring tape, use the calculator below. It uses the Navy body fat formula.
