DXA Scan Results

In December 2015 I got a DXA scan to get a sense of body composition during my first ever intentional cut (or perhaps it was my second ever if you count my experimenting with keto under a deficit in college). It was fairly inexpensive — I did it through BodySpec’s West LA location for $42.50. The whole procedure took about 10 minutes, plus another 10 to chat with the technician. Interpreting the results is a little iffy without knowing how they arrived at some of their numbers and conclusions*, but it’s still useful and interesting information to have.

Here are the scan results:


And for reference, here are some derpy scantily clad photos of myself a couple days after getting the DXA scan. The first is me in a gym locker room before going for a swim:

i0hqtfwAnd here’s Kate lifting me up during that swim (with legs visible):2015-12-28 11.41.25.jpg
and a (flexed) leg-shot:Legs.jpg
and a (flexed) back-shot:

UPDATE: Here’s a couple of “progress photos” from 1y later, by which I mean almost nothing changed (aside from my haircut). 2016 was pretty busy for me so I didn’t have much time for exercise. Oh well!


Diet and Exercise information

Diet: Mostly lacto-vegetarian. I’ll usually have some protein powder in my coffee in the morning, and once or twice a year I’ll eat a small piece of meat or a cookie with an egg in it or something. I don’t really track calories. I do take some basic dietary supplements, however (protein powder in coffee, creatine, multivitamin, omega-3s, etc.).

Exercise: I engage in resistance training 2-3 times a week except when traveling, or when I’m really busy, or when I’m focusing on some other athletic goals. I’ve no real set routine, at least not consistently, but depending on the lift and how I feel I’ll follow something like 5/3/1 or 5×5 for a time. Currently nursing some back and shoulder injuries (from lifting and snowboarding) so lifts aren’t too hot — around 225×5 for bench, 245×5 for front squats, and 365×5 for deadlifts. Hopefully I can heal up quickly and get back into the 3/4/5 plate range (for the big 3). I can do around 20 unweighted pullups, too, and Bulgarian split squat around 220 lbs (with DBs). I also walk 5-10 miles a day and go on 10-20 mile hikes on the weekends, and occasionally backpack for 1-10 weeks at a time. Sometimes I’ll do other athletic-y stuff too (e.g. climbing, watersports, dancing, slacklining, etc.). Been lifting on and off for the past 6ish years, and did tons of trailrunning before then. Recently, I’ve been trying to get back in to running, with my current target a comfortable sub-5 minute mile. Right now my mile time is in the high 5s and I’m pretty pooped after.

Overall, the DXA scan estimated my body composition to be around 15% fat by weight. This is around where I expected it to be and in line with caliper estimates (which are well known to underestimate bodyfat, putting me around 11-12%). My current goals are to lose another ~10 lbs or so and lean out my midsection a bit, with a target DXA BF% of around ~12%. My bone density is good for my age demographic, which was expected given the fairly active lifestyle I lead. It’s also nice to see that my right and left appendages appear fairly balanced in total muscle amount. My A/G ratio and VAT could be better, but probably aren’t worth worrying about too much. My Total Mass was estimated/measured to be 191 lbs, but my weight can vary between 170 and 220 lbs depending on what I’ve been doing (if I’m backpacking it plummets, if I’m bulking and lifting it shoots up).

*Some questions I had but am still a little unclear on include:

  • The scan gives point estimates for all the measurements, but what’s the uncertainty about those estimates? The tech who chatted with me mentioned an interval of +/- 1%, and from what I could tell this was the total range of values obtained from a single individual tested multiple times in quick succession. So I guess the test is pretty precise/consistent, but how accurate is it? Systematically, how close to the “true” values are these measurements? He said they calibrate their scanner using blocks of known densities, but how representative are these blocks of the complex, overlapping hodgepodge of materials that is the human body? How much uncertainty is there in the (according to the guy) “algorithms” they use to calculate the estimates from whatever data the scanner picks up? How much variation is there in the values obtained from a single individual across multiple days, levels of hydration, GI contents, etc. (he mentioned they ran the test before and after one of their employees drank a few liters of water and it didn’t change the numbers much, but chugging water quickly seems like it might have different effects from being mildly dehydrated over the course of a week, say).
  • Similarly, how accurate is the “Muscle Balance Report”. Evidently I have about the same amount of lean mass in my right and left legs, but I can do a dozen more pistol squats with my right leg vs my left leg. Is this indicative a muscle imbalance elsewhere or is it just a matter of balance, muscle fiber recruitment, and coordination?
  • According to the guy, an A/G ratio of 1 “unhealthy”. What does health entail here, exactly? Are there sex differences in what the “healthy” range is for men compared to women? He wouldn’t elaborate much (“the results of this test do not constitute medical advice”). Does some A/G ratio X or amount of Android Fat Y correspond to some Z increased risk of heart disease or something for my demographic above some baseline? Since more of my fat is android, losing more fat would presumably lower this ratio.
  • Likewise, if my VAT should be as low as possible, what does a non-zero VAT imply? A smaller person would presumably have a lower amount of VAT, so why isn’t this number adjusted for some function of weight as a proxy for size of organs or something? Or is it the absolute amount that matters? And what are the quantitative health implications of higher bone density?

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