Joe Miller of the Raleigh News and Observer has been chronicling his fitness activities of late. The other day he had this choice complaint:

Yesterday, I had a story in the paper about 10 things you could do to lead a healthy life. Included was a reference to the Body Mass Index, the formula for which was inaccurate, for which I am sorry (especially to anyone who attempted the calculation and discovered they had a BMI in the 200s). To determine your BMI, divide your body weight in kilograms by your height in meters squared. Or, since you’re already online, use the calculator at http://nhlbisupport.com/bmi/.

That said, don’t. The BMI is a deceptive figure. Case in point: I am 5’9″ and weigh 165 pounds. I am not a big guy, by any means. I’ve been called “emaciated” by someone who knew me when I was a bit larger and have had an ongoing debate with a 7-year-old who insists that I’m skinny. I’m not skinny. Nor am I borderline overweight, as my BMI would suggest. My BMI is 24.4; 24.9 is the cutoff for being overweight. Last spring, when I was 30 pounds heavier, I was borderline obese. Borderline obese ó and yet I managed to participate on a two-man team in a 6-hour mountain bike race. Yeah, I was a little chunky. But I was also in relatively decent shape. I’m still in OK shape, despite, according to the BMI, teetering on being overweight. And, according to the BMI, I could weigh 125 pounds and still be considered a “normal” weight. If I lost 40 pounds, I’d be beyond emaciated. I’d likely be on an IV ó but at least I’d be in the “normal” range.

Like Joe, I had one of those “borderline obese” BMI ratings before I lost 30 pounds. It’s annoying to be told you’re “obese” when in fact all you’re doing is carrying about 20 extra pounds around the gut. There is one upside to being near that border: you don’t have to suffer nearly so much getting down to a more healthy weight. You have to burn 35,000 excess calories to lose 10 pounds (that’s 87.5 hours of hiking at 400 calores per hour); imagine what you’d have to endure to take off 50 or 100 pounds.