Can You Trust Those Calorie Counters? ..................................................
At the gym one day, Suzanne was pumping away on the stair-climber next to a
very fit woman. For a brief moment, the woman looked away from her machine
to say hello to a friend. When she looked back, her 45-minute workout had
ended, and she had missed the final calorie readout. Horrified, the woman
uttered several curse words and then stormed into the locker room — as if
not knowing her exact calorie burn negated the entire 45 minutes of effort.That may be an extreme case, but most of us do get a psychological boost
from knowing how many calories we just burned. There’s just one problem:
The information may not be accurate.For the most part, the formulas used to calculate calories burned are derived
from tests done on healthy young males — and in some cases, elite athletes
working near their maximum effort. This does not always translate accurately
for the rest of us. For instance, a recent study conducted found that fitness
equipment readouts may overestimate calorie count for obese women by as
much as 80 calories for 30 minutes of moderate intensity walking.Other research has found that calorie predictions are skewed even further
if you lean your body weight against the handrails, grip tightly, or otherwise
position your body on a machine in a way that makes the exercise less stren-
uous. Some studies have shown that calculations can be off by as much as 50
percent.Sometimes it’s not the formulas or your technique that skew the calorie
count; it’s the deceptive marketing strategy of the machine’s manufacturer.
A researcher for one cardio-equipment manufacturer admitted to us that his
company intentionally boosts the calorie information by as much as 30 percent
so that people may, subconsciously, prefer their machines over other brands.We suspect that elliptical machines (described in the “Elliptical trainer” section
later in this chapter) have particularly generous calorie readouts. Case in
point: When Liz does a fairly easy elliptical workout, the machine tells her
that she burns 12 calories per minute — a number that seems suspiciously
high. In fact, in order to achieve the same calorie burn on the treadmill (known
to be an accurate machine), she needs to run at a brisk 8 mph, a pace that
shoots her heart rate way up into the huff-and-puff zone. We’re skeptical that
these two workouts are equivalent.The most accurate machines tend to be the treadmill and the stationary bike
because the contraptions have been so well studied. In recent years, stair-
climbers have adjusted calorie estimates drastically downward to better
reflect reality.The bottom line:Realize that the calorie figures are simply estimates.128 Part III: Getting to the Heart of the Matter