One Pinch Fat Test
Is your weight loss or gain muscle or fat? With practice this test takes less than ten seconds. And you can do it every day.
Enter your pinch and weight here:
Results
Percent fat: —%
Lean mass: —
Fat mass: —
Results
Percent fat: —%
Lean mass: —
Fat mass: —
Instructions
Being as consistent as you can, take one vertical pinch of skin (and fat) 2 cm (approx 1 inch) just to the right side of the of the navel. Pulling the skinfold away from the underlying muscle, measure the thickness with your skinfold caliper (or eyeball it if you don’t have one). Maintaining the hold with your other hand, take the reading about halfway to 2/3 down (deep) into the crest of the skinfold. Enter that thickness, measured in mm, and your bodyweight in either pounds or kilograms below.
If you wish you can take 3 measurements and average them, or take the middle one. I only do this if it seems off, or I think I got a bad pinch. The leaner you get the more accurate this becomes with variation between pinches being just a fraction of a millimeter. In my above photo I’m at about 4.5 mm. In my experience, a solid 6-pack is less than 5 mm, and tenths of a mm do matter at the low end.
I do it every morning and it takes about 10 seconds. Try doing that with your DEXA and you might get cancer because it’s radioactive.
You should get faster and more accurate with practice. Though in the research they always measure the right side, I don’t think it matters right or left, and I recollect one study that said as much.
Two forms are given below so you can enter your data as they are now. And then again making whatever future assumptions you wish regarding inputs or outputs.
About calipers
I have a milk crate full of most of the popular calipers available. The Lange is by far my favorite for both convenience and accuracy to the tenth of a mm. And the Lange is the exact one used in maybe half of the research studies on skinfolds (which is a lot of studies). It’s a bit pricey, selling new for about $250, but you can find good used models in the $50 range on ebay. The plastic SlimGuide caliper is a decent low-cost alternative ($20-30), and SlimGuide knockoffs (the knockoff’s knockoff) I’ve obtained off temu (~$7, pre-tariff) with identical profile working just as well. But I only know this because I have the Lange to compare it too. The Sequoia is cheaper than the SlimGuide, but more expensive than some knockoffs, will take consistent measurements, but its spring is too strong, so will measure you about 1 mm leaner than you actually are. I don’t recommend the Sequoia for that reason, but if you have one it will let you know if you are gaining or losing. The V-shaped “Fitness 3000” style calipers don’t work hardly at all in my experience, be they name brand or knockoff, and I have several, so I don’t think I just got a bad one.
