This week we take up the question the Crew hears more than any other, with the sole exception of "Do you guys really do all this stuff yourself?" Since we've learned to dodge that one, we'll take Number Two: How do I figure out how many calories I burn?
This is an area loaded with hooey and misinformation. Let's take it from the top.
Ms. Example Given: Moving, not muscle, determines her calorie burn.
_____The Moving Crew_____
At Play With a Madman (The Washington Post, Mar 29, 2005)
On the Treadmill: Keep Hope Alive (The Washington Post, Mar 22, 2005)
Calculating the Curves (The Washington Post, Mar 15, 2005)
Does Bush Put His Budget Where His BMI Is? (The Washington Post, Mar 8, 2005)
Out of the Running? Friends Can Help (The Washington Post, Mar 1, 2005)
The Moving Crew explores some facet of fitness and offer ways to overcome the excuses that keep so many of us desk- and sofa-bound. Join them, every other Thursday at 11 a.m. ET.
In a typical day, you burn calories four ways:
basal metabolic rate (BMR), or calories used when sedentary;
thermal effect of feeding (TEF), or calories burned digesting food;
physical activity (anything you do besides sitting: walking, piano playing, shadow boxing); and
excess post-exercise oxygen consumption (EPOC), that oft-hyped afterburn from a workout.
To see how these might add up, let's say hi to Ms. Example Given, a 5-foot-5, 45-year-old who weighs 135 pounds and consumes 2,100 calories worth of food and drink a day. (Caveat: The figures below are approximate, vary widely between individuals and are subject to debate in the field. We're doing the math because you asked.)
First: You can do little to change your basal metabolic rate, despite what some dietary supplement makers say. Worse, BMR declines with age.
As for the talk that muscle burns more calories than fat: Muscles burn six calories per pound per day while fat burns two calories per pound per day. So, yes, muscle is more industrious than fat. But even if Ms. Given converted two pounds of fat into two pounds of muscle -- no mean feat -- she would burn only an extra eight -- eight! -- calories a day through BMR.