Oh yes, it's that time again, my annual body composition post. Last year I talked about self acceptance and you got to see some of my heavier photos, those are always fun, eh? This year I am going to get all data crazy on you. I've always wanted to go have one of those DEXA things done. They always use them on The Biggest Loser to tell the people "you are 50% fat" etc etc. I wanted to see what my skeleton looked like and everything I have read said that it's the Gold Standard in body fat percentages. There is a mobile DEXA unit that comes to my gym once a month so I signed for for a slot, paid my $70 and showed up on time.

I wasn't nervous...ok, I was a little nervous. Mostly I was excited and really intrigued.

Inside the van was the DEXA machine. It's a low dose Xray machine as I understand it. You lay there really still and it goes up and down and up and down a ton of times. I would say it takes about 5 minutes.

Then the technician does her work which I'm not sure what that is. Then she printed out three pages for me. I kinda tried to ask her some questions and she said "I'm not really good at explaining the numbers." So I figured that wasn't part of the $70, went on my way and figured I had a bit of research to do.

Check me out! How cool is that...it's me, and I look very skeletal! Very halloween, and I don't see a lot of fat there...looks pretty lean and good to me. I like the ribs, look at all those ribs, I think I have a barrel chest. Spine looks nice and straight. Look at me, trying to act like I know stuff...

So then come the results. Honestly it's a lot of numbers that I don't quite know exactly what they are, but you can see pretty clearly that the DEXA machine (now affectionately nicknamed "Liar") thinks I have 30.5% body fat. What? Wha? Wh?W? WTF?

The following numbers are quite a hoot to look at as well, check out how fat my left arm is compared to my right. I get that I am right handed and all, but really...I don't write that much anymore...just a lot of typing really. My right arm is the wonky one in the pool too...maybe it's too lean and doesn't float enough?

So of course immediately when I get home I strip down to my birthday suit and make Troy come take pictures of all the scales I have at home and what they think. I used to not even have a scale but now I have a few, and I love them all equally (not really).

First off, my uber-favorite scale, the Withings Scale. This scale is totally awesome because every morning (that I remember) I get on it and it takes my weight, body fat % and BMI. BUT THEN...it automatically uploads my data to the Withings site, the Withings app on my iPhone, AND to Training Peaks, using my wi-fi network at home. Yes, my scale is wi-fi! This seems silly, but it's actually a really nice feature. So what did Withings have to say?

Humm, Withings thinks 24.6%. So how do scales calculate Body Fat %? Well, they use what is called bioelectrical impedance analysis, which clocks the speed that electricity moves through you and based on the levels of resistance it can determine fat vs muscle. Everything I have read says that DEXA is way more accurate.

I pulled out the Tanita Scale that I have as well. I used to use this all the time and have noticed since getting the Withing that it was usually lower than the Withing. The Tanita thought:

Can you read that? It says 20.9%. It also thinks I gained 0.6 pounds in the 12 seconds it took to go from one scale to the next.

So, what do I think of all this? Other than I paid $70 for a picture of my skeleton? Humm, 30.5%, 24.6%,20.9%. That's a tough one. I guess what I think from a personal standpoint is that it's just a number. I know that I am fit, and lean. I wear a size 4, I'm healthy, and I'm not at risk of any serious conditions that I know of.

I think the bigger issue I have is with the recommendations and numbers that have been put out there from the various institutes on health (which in and of themselves are hard to track down):

I found this:

For women, they are considered obese if their body fat percentage is 32% or above, for men this number is 25%. Acceptable levels of body fat include 25-31% for women and 18-25% for men; while athlete’s body fat percentages usually range between 14-20% for women and 6-13% for men.

I also found this:

For women:

  • The recommended amount of body fat is 20 - 21%.
  • The average American woman has approximately 22 - 25% body fat.
  • A woman with more than 30% body fat is considered obese.

Either way, the DEXA is telling me I am either at the upper limit of acceptable, or I am considered obese. I think my favorite is "the average woman is 22-25%". But the CDC has just revealed that "1 in 3 of US adults is obese". BMI data was used to make that claim, not Body Fat %. I just think there is a huge disconnect here. HUGE!

Clearly the Body Fat Percentage recommendations are missing the mark when it comes to supposedly accurate DEXA data. I'm not sure what testing system the recommendations are based upon. While I know I am fit and healthy and I don't need to worry myself about the latest forskolin benefits for fat loss but still, it bums me out that the lines of health seem to be so blurry. I've heard that BMI is not an accurate indicator of health, I would argue that Body Fat % is not as well. So much research, but so little actual facts.

No 2011 Body Composition blog post would be complete without some photos of my "12 days until Kona Ironman World Championships" body. I'm always a little embarrassed to post these, but I do think they are cool to look back upon and I would urge any of you training for an Ironman to take a few photos in your final days of training.

Not Obese...

I'm really curious on all of your thoughts here! Have you had any body fat testing done? Have you found it to be accurate and/or helpful in determining your proper weight or leanness for a big athletic event? Do you think the information out there is helpful and plentiful? Do you think the DEXA is correct? Do you think the health recommendations are correct based on the DEXA results I saw? I'm so curious what you think!

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