BEFORE WE OFFER suggestions on what to eat, we need to
figure out how much to eat. I'll confess right up front that we're
going to use rough estimates here. The numbers we use-and by
"we," I mean Cassandra-are based on the Owen equation, one of
several ways to estimate your resting metabolic rate without
access to high-tech equipment.
The number you get by using the formula isn't pulled out of
thin air-the Owen equation ranked as the best for normal-weight
women in at least one study. But there is no single measure that
works best for all women. Other formulas are considered better
for obese women, for example, or for different ethnic groups, or
for athletes.
And then there's the issue of the amount of activity you get in a
day, and how much you move in general. Studies have shown that
people who fidget burn more calories throughout the day than
people who don 't. Drinking water, chewing gum, sleeping more
or less than usual ... we could probably come up with dozens of
reasons why you or anyone else would have a metabolic rate
that's different from the ones the formulas predict.
Our goal is to give you a starting point, after which you can
manipulate calories up or down, depending on how the initial
calculation works out for you. We'll give you detailed instructions
on how to cut calories if your calculations suggest you should (as
I wrote earlier, I think we' re all pretty proficient at adding them) ,
and how often. First, though, let's establish some baseline
numbers. In the following example, I'm using a fictional woman who 's
five-foot-four, 140 pounds, and thirty years old.
Step 1. Weight in kilograms
Weigh yourself. First thing in the morning is best. Now divide
that number by 2.2 to get your weight in kilograms. Our 140-
pound woman weighs 63.64 kilograms, which I'm rounding up to
64.
Step 2. Resting metabolic rate
Run this equation:
795 + (7. 18 x body weight in kilograms) = resting
metabolic rate
Our sample woman has a resting metabolic rate of 1 ,254 calories.
That's the number of calories she 'd burn if she did nothing and
ate nothing all day. (If you're wondering where the constants in
that equation-795 and 7. 1 8-come from: The researchers start
with an accurate measure of the resting metabolic rates of the
subjects in their studies, using high-tech equipment with tonguetwisting names like "indirect calorimeter." Then they find the
mathematical formula that most accurately predicts those
metabolic rates.)
Step 3. Body mass index
Find your body mass index, or BM!, in the following table. BMI
is a height-and-weight calculation that doesn't take into account
your ratio of fat to muscle. So, like everything else in this chapter
so far, it's more useful in general than it is when we're talking
about a specific person.
Our five-foot-four sample, Step 4_ Daily-activities multipliers
Now, use your BMI and age to figure out how many calories you
burn on two different days, depending on whether or not you
work out. You 'll notice the chart has an extra line labeled
"strenuous work and workout day. " If you're really active
throughout the day-you work in construction, say, or you play a
competitive sport with an hour or more of daily practice-and
work out that same day, you'll multiply by a higher number than
you would if you have a typical deskjob.
Commentaires
Enregistrer un commentaire