The scale has officially been dethroned as the ultimate measure of fitness. While you can see weight loss/gain in numbers on a basic scale, there are so many things it doesn't take into account: muscle mass, water weight, etc. (Just take a look at this blogger's before and after photos where she weighs the same.)
What does matter: body composition—the percentage of your body made up of fat versus lean mass (muscle, bones, organs, etc.). While you can judge a certain amount about your body composition by looking in the mirror (hey there, six-pack), the only way to truly track your body composition is by getting a body fat test. (You also need to know these five surprising things about body fat.)
But as trainer Anna Victoria demonstrates in her latest vlog, that's easier said than done. Anna tested six different body fat measurement methods, and her body fat percentage ranged from 14.2 percent to 26.4 percent, depending on the test. So, as with the scale, you have to take that number with a grain of salt.
The first two tests use bioelectrical impedance analysis (BIA). This method sends electrical currents through your body to measure the amount of lean versus fat mass. One is an at-home platform that looks just like your usual scale. The second, usually done at a gym, is a handheld device. (You can also buy one to have at home.) She also did a skin fold caliper test (the old-school method for fat testing) in which a trainer will pinch a certain number of points on your body (stomach, thigh, arm, etc.) to calculate your body fat percentage. Next up, the DXA scan. This is the current gold standard for measuring body fat, but it costs about $45 per session. Traditionally used to measure bone density, the machine uses weak X-ray beams to detect the composition of every square inch of your body. Then there's the Bod Pod—a little pod you sit in that measures the volume of air you displace to calculate your body composition. This is the most expensive option, costing Anna $95. Last is hydrostatic weighing, where you submerge yourself under water. That cost Anna about $50. (Here's the full list of the best and worst ways to measure body fat.)
Anna Victoria's Body Fat Percentage Tests
BIA scale (at-home): 26.1%
BIA handheld scale: 18.8%
Skin fold caliper test: 23.4%
DXA scan: 23.5%
Bod Pod: 26.4%
Hydrostatic weighing: 14.2%
"At the end of the day, there is a margin for error for all of these tests," she explains. That being said, she recommends the DXA to anyone who is able to find one nearby, because it's the most scientifically accurate and precise. That's why DXA scans are often used in research settings to validate other body fat measurements, according to the Harvard T.H. Chan School of Public Health.
Whichever method you go with, Anna recommends staying consistent if you're using it as a way to measure fat loss. (For example, if you have the same trainer use the same skin fold test, your results will be more accurate than if you get a DXA scan and then try to compare it to a BIA handheld scale later.)