12 October 2007

Measurements

I took the AF physical fitness test yesterday and scored another 2.5 points higher than last time. My total score was 89.5, so I was just 1/2 a point away from being in the "excellent" category. If I'd shaved 9 seconds off the run, I would have had another 1.5 points (and I think I would have done it too, if there'd been anyone running in front of me, but I was the fastest guy on the track). It's my highest score ever (again), and I'm very happy with the outcome. I maxed the pushups and situps and lost an inch on the "abdominal circumference" measurement.

But my point isn't to brag. I'm actually thinking about how & what we measure, and the decisions we make based on those measurements. See, in addition to doing very well on the test, I also calculated my Body Mass Index (BMI), just out of curiosity. For those who don't know, the BMI is basically a ratio of height and weight. My BMI is 27.6. Anything over 25 is considered "overweight." But here's the thing: the BMI was only intended to classify sedentary individuals with an average body composition (not active, athletic types) - and we're using it for a lot more than that.

In fact, Wikipedia says "BMI has been used by the WHO as the standard for recording obesity statistics since the early 1980s." Yikes! That sort of makes me wonder about the whole obesity thing. If a guy like me falls into the "overweight" category, I wonder how may people in the "obese" category really don't belong there. I have no idea or any data - I'm just skeptical.

Yes, there are a lot of big people around these days, but that's an anecdotal observation, not a statistical or scientific one. It seems to me we should define obesity as having something to do with body fat percentage... but that's a harder thing to measure than a simple height/weight ratio. Do we end up measuring what's easy, rather than what's meaningful?

Am I missing something here?

2 comments:

Deb said...

I haven't had my BMI done for at least 10 years and probably won't have it done anytime soon. :) Need to lose the baby weight first! :) Although, I now wonder what it would be as a pregnant woman of twins?!?! HUM.....

Anyway, congrats on improving your time....that's great! :)

Bruce said...

You're correct that the easy rather than meaningful measurements are done. The Dept of Labor's Unemployment numeber is not a measure of the the total unemployed including those that ran out of benefits, those underemployed, and/or those that have given up but the count of the number of individuals that are still drawing unemployment benefits. In 1999 I discovered that the employment numbers given by the same Dept of Labor admitted that their method of determining job growth and shrinkage by using the size of the Sunday classifieds of a few key metro areas might not be as accurate as it might once been due to the Internet. DUH.