If you’ve been following this blog at all, and I’m sure you haven’t, you’ll know that I’ve been testing my body fat at least once a month to track my progress towards my goal of being 6% body fat by the end of September.
Something you may have been curious about is how exactly I’ve been testing my body fat content, and how accurate that number is.
I’ve always been curious myself as to how accurate my readings were. If they were artificially high, then obviously I wanted to know so I could feel one step closer to my goal. If they were coming in too low, well… I guess I didn’t really want to know in this case. I’m happy to live a lie.
Let me point out that there are many different ways of getting your body fat tested, and most of them are considered more accurate than the two that I’m facing off in this article. However, the most accurate all seem to involve seeing a doctor, gypsy fortuneteller, or some form of specialist (You can get a pretty exhaustive list of the different methods here).
Well I don’t want to have to bring my health insurance into this, and I’m pretty sure you don’t either. So that gives you a couple more economical options:
- Calipers (the old fashioned, time tested method)
- Bioelectrical Impedance testers (Handheld, and scale)
What I’ve been using is a handheld bioelectrical impedance tester called the Omron HBF-306C
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I love this thing for several reasons:
- It’s easy to use
All you have to know are your basic stats: age, height, weight, and sex. If you don’t know the answers to these basic questions, or how to find them out, your parents have failed you miserably.
When you power the unit on, it will prompt you to enter these numbers, and after doing so will say “Ready”. All you do then is stand up straight, hit “Start”, grasp the handles, and hold it away from your body with your arms straight out in front of you until it gives you a reading (usually about 5 seconds or so). That’s it. Done.
Keep in mind that the best time to weigh yourself and do the test is in the morning before you eat anything. This will generally give you the most accurate reading.
- It’s extremely portable
Do I really need to talk about this one? You see the picture. It isn’t made of plutonium. The thing probably weighs a pound, if that. Just pop it in your gym bag if that’s where you weigh in and you’re good to go.
- It’s cheap
I think I got mine for like $30 or so. Before buying one though, I’d check with the folks working at your gym to see if they have one. You might be able to use theirs. Why spend money if you don’t have to, right?
- It’s great at parties
I love to play the “I bet you’re fatter than me game”. Talk about a crowd pleaser that’s good for any self-esteem…
All jokes aside, this thing seems pretty solid. However, if it isn’t accurate, who gives a crap. I might as well just slap my belly and count the jiggles (I initially spelled that as “giggles”. Would’ve been funnier, so I saw it fit to mention).
So I decided to see how this thing measures up to the tried and true body fat calipers. While calipers are obviously dependent on the knowledge and skill of the person administering the test, they have been shown to be highly accurate in the hands of a trained professional.
Having a trained professional who was crazy enough to meet me at 6:45am, I went to Amanda for another body fat test this morning. She administered the test several times to ensure accuracy, and hey whaddya know: I’m down to 7.8% according to the calipers. Hey I like these things. Last time she tested me (which was a little over 2 weeks ago) I was at 9.1%. That’s solid progress.
After I got the caliper test, I went directly to the gym to weigh in and test myself with the 306C. I weighed myself 3 times just to be sure of the number, and used the 306C several times to get a solid average.
My weight: 181.6. Nice.
Body fat: 8.6%…. Not quite as nice as I’d hoped, but still progress from my last reading.
From this, you can see that the figures between the two tests were fairly close:
7.8 on the calipers, 8.6 on the 306C.
Less than a full percentage point of difference, which most people can live with. But which reading am I going to put my money on?
As far as an official number, I’d have to say calipers. Why? And no, not because it’s the lower number (though I am pretty excited about that)…
I have to believe that calipers are better testers of overall body fat. The samples are taken from various locations on your arms, upper body, midsection, and legs, giving a fuller picture of your body’s fat content. These numbers are then averaged to come to your overall fat percentage. Sounds like a solid formula to me.
With the handheld unit, it only tests the fat content in your upper body, and from this reading, makes assumptions about the fat content of the remainder of your body.
Why do I say this? Well it’s sending an electrical current from one electrode to another, or from one hand to the other. If my understanding of electricity is at all accurate, then the electrical current will take the shortest possible path to close the circuit. This means that the test runs from one hand, down your arm, through your chest, and back up the other arm to the opposite hand.
Put simply, it measures the fat in your arms and chest. That’s not exactly what I’d call a full body sample. While I’m sure the equations it uses to calculate the rest of your body are as scientific as they come, it’s impossible for it to account for the infinite number of differences between people’s bodies, and in the end is just an estimation.
Does this make the 306C worthless? Of course not. As shown, it’s fairly accurate. Plus, with all the pros I stated in the beginning, it seems a good option for the self-tester. After all, who has the time or resources to grab a personal trainer every morning or so to do a caliper test?
I plan on testing with the 306C weekly from here until the end of September to make sure I’m progressing. However, at the end of September, you best believe I’m going to recruit Amanda’s help for a final caliper reading.
Bottom line: The Omron HBF-306C
may not be quite as accurate as the calipers, however it’s low cost, ease of use, and portability make it a solid choice for self-administered body fat testing.