Living by the Numbers
Credit: Illustration by Eddie Guy
I'm 48, and my wrestling match with my metabolism has gone on for 17 years. Early victories gave way to losses after I turned the corner on 40, but I battled back and for the last half decade it's been a hard-fought draw. During that time, I've weighed 195 or so, but at 6-foot-1, I've carried it pretty well. Still, my body mass index consistently put me just north of normal whenever I plugged the numbers into one of those online calculators. And if you haven't calculated your BMI recently, just north of normal is also known as "overweight."

BMI has its limitations, especially for athletes who pile on sheets of lean muscle, but for most of us, it's a reliable indicator. To give you an idea of the calibration, Iggy Pop's BMI is approximately 22.4, solidly in the "normal" range of 18.5 to 24.9. John Candy's when he died was around 41.2, above the "obesity" line of 30. Mine was 25.7, a mere 0.8 into "overweight" territory, but when you spend 17 years working out three days a week and watching what you eat and still come up a tiny bit overweight, it gets on your nerves.

Or it would, if I'd really been working out three days a week and watching what I ate. But routine breeds boredom, and over time my virtuous schedule had slipped. Now a good week meant I was in the gym once for strength training, and spinning once or twice for cardio. I had no idea what my diet was anymore, other than delicious.

And so, thinking there must be some fitness equivalent of Google Maps, I load up on tech and dive into the world of numbers. I start with the Withings Body Scale. It's a smart scale – WiFi enabled and digital, and it not only calculates my weight but also uses a low dose of electricity to suss out my BMI and fat mass – and it's designed with the minimalism Steve Jobs bequeathed to the world. Setup is simple enough, and so is the way it works: Step on the scale and a tiny electric current goes through your feet, up to your head, and back to the scale. Fat slows it down. Now Withings knows your insides and will use your WiFi network to send the results to your computer and an app on your phone. Over time, the numbers are graphed into a clear picture. In keeping with the new age of social media (and the old traditions of shame as motivation), you can also tweet the results of every weigh-in, though this feature is mercifully disabled on startup.

Withings wants me to weigh in once or twice a week at the same time, before I've had anything to eat or drink, but tonight I step on just to see how it works. Success is instant: I've set up my starting weight at 195, but I weigh 193. I've just lost two pounds! My BMI is 25.6, just 0.7 north of where I want it. I have my first goal. It will not be my last.