Friday, August 8, 2014

Taking the Plunge - BodyFatTest.com

"And now for something completely different"

We've been using MyFitnessPal for tracking our caloric intake and FitBit trackers for our step counts for a few years now with good success. I posted a blog last year about how we started and how important it was to keep track of things, even if things are going well. Now that we're in maintenance mode and training to get faster, we're taking more steps to get even more information to form a baseline. Our next adventure - Body Fat measurements.

Why should you care about body fat? On the extreme high end, excessive body fat can cause a variety of issues like heart disease, high blood pressure and type 2 diabetes, not to mention stress on joints trying to support the added weight. Conversely, you can actually have too LOW a body fat percentage and be susceptible to chronic fatigue, decreased athletic performance and increased risk of infection.  Overall, body fat percentage is just one other way to measure overall health.

There are a number of ways to measure body fat percentage. The quick and easy way is a calculator based on measurements, gender and height. Active.com has a variety of calculators including the sometimes over-generalized BMI, a range for ideal weight and your projected caloric intake to maintain your body weight. For the record, my calculated BMI is 23, Body Fat is 13%. I think their 2512 calories per day (for 'low active' level) for me is overly generous, but I'll go ahead and remember to order dessert the next time I'm out for dinner. 

Our Fitbit Aria scale gives a body fat reading, but for the last year, it's been unreasonably low for me. I mean really low. 5% pretty much all the time. That level is telling me that I have nothing other than "essential body fat" required to keep my body functioning. The Aria measures body fat by electrical impedance and can be affected by hydration levels in the body. Accuracy is directional, but not something you want to depend on.

Last week, Clorox had an in-house wellness vendor using an e-InBody machine which uses a similar method. Again, since the impedance method can be affected by hydration, readings can vary widely. Having the device in the cafeteria after lunch may or may not have been the best way to do the testing, but at least people used it.  I came in at a reading off 11.8% body fat.  The vendor gave me a standard chart of 'normal ranges' saying I was getting close to the bottom of where I should be. Naturally, I took that advice and went to In-n-Out burger for lunch. I walked a half mile both ways. And ordered a protein style cheeseburger and tossed half of the fries before I sat down.

The gold standard for measurement is Hydrostatic Body Fat testing (aka, 'the Dunk Test'). We missed a chance last year at Sports Basement Walnut Creek because it was on a weekend we were out of town for a race. I know. Big surprise.

First, we have to find the truck (Thanks, Al for giving us the heads up!). Body Fat Test runs a mobile testing center that parks outside of gyms, sporting good stores or other locations to conduct the test. Appointments are encouraged since the walk-up service can be hard to time well. Check their calendar for national times and locations. Northern California test schedules can be found here.


Outside of Anytime Fitness in Newark. You can't miss it!
We showed up for our 4:30 appointment with Mike. The trailer has two changing areas, a scale, the dunk tank, a scale, a laptop station where the measurements get turned into the analysis for you to take home, share or post on a blog. We were told to bring a swimsuit that won't catch air bubbles since buoyancy is the key measurement for this test method. It's not as sensitive to hydration levels as the Aria or e-InBody, but they suggest not having a big meal within an hour of testing.  The test costs $49 per person for the first time and $39 for a retest.

Note to self. Refrain from dairy... or burritos.. before this test.
There are two variations of the tank configuration. In one, the subject is put in a seated swing. BodyFatTest used the prone tank with a wide scale. It has the advantage of using less water (about 10 inches deep. The water is filtered, chlorinated and dumped at the end of each day. It's also at a comfortable 90 degrees.The grey belt around my waist is a weight belt to ensure total submersion. To get the best result, you're supposed to blow out ALL of your breath. Mike would pound on the side of the tank when it looked like you were out of breath so you could come back up. It took me the three tries to get a constant result.  It took Susan a few extra tries to relax enough to feel like it was safe to stay under. Note to self: if doing this in pairs, let the water-lover go first to build confidence.


It looks scarier than it actually is, considering I'm face down in a tub of water and I've totally exhaled every bit of air that I had in me. The short sleeve shirt and sock tan lines, you'll just have to deal with.

Results? 8.8% Body Fat, somewhere in the 97th percentile, well into the "athletic range" and safely above the 5% lower level of 'essential fat'. An added benefit of this test is knowing my Base Metabolism Rate which is what my body would need to maintain weight if I never even got out of bed. It still sounds pretty high to me at 1920 calories per day. Even MyFitnessPal calculates the BMR at 1583 calories. 

After all this, I'm going to choose to stick with my current net calorie target. I have a feeling I underestimate my portion sizes and I try to add more steps on my FitBit. We'll come back and retake the test in six months or a year after our race schedule has a month break in December. Maybe we'll build up some 'room for improvement'.

Ron will be going to his first Spartan Race on Saturday in San Francisco at AT&T Park. No, he won't be racing. He'll be working as a volunteer security for The Biggest Loser Run/Walk participants VIP tent. Since its a local race, I still plan to get my slow mileage in by walking to Bart, taking the train to Embarcadero and walking to the race. Even though parking is only $10 at the event plus the toll across the Bay Bridge, it looks to be a beautiful day to be outside.

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