Fat
Loss Basics:
Food and Exercise
A very simple formula explains bodyweight:
Bodyweight =
what goes in (food
energy)
–
what
goes out (basal metabolism* &
exercise).
*
The
calories burned to fuel the body’s basic biological functions
It’s
like an hourglass filling with sand (energy) at the top,
and emptying at
the bottom with energy output.
If
you pour sand in faster than it goes out by eating more food
than you need, then
the hourglass fills up, and you get fatter.
If you increase energy output by increasing expenditure,
then bodyweight
falls.
The
following simplified daily energy requirement
(or “calorie demand”) breakdown
shows key factors
affecting the amount of food energy used:
60% from basal metabolism (affected by
muscle-to-fat ratio)
30% from activities (including
exercise)
10% to digest food
Body
metabolism also matters.
The more fit a person is, the higher his metabolic
rate.
And gender makes a
difference
—the basal metabolic rate of women is 10% lower than that of men,
partly due to differences in the percentage of body fat
and muscle mass
(“muscle-to-fat ratio” or “body composition,”
which can be assessed
before your workout with a quick skin-fold test).
Traditional
dieting is a double-edged sword.
As you reduce your intake of calories,
your body becomes
more efficient at using energy. It decreases energy
consumption
in order to survive. As your body weight falls, you expend
less energy.
This means that you decrease your metabolism
because your
mass is smaller,
in addition to your body’s more efficient use of
calories—
this in essence promotes the infamous “yo-yo” effect of
re-gaining lost weight.
Exercise
is the solution! People
utilizing proper nutrition with exercise
do better because exercise burns
calories and burns off fat.
Exercise also builds muscles that use more
energy than the same weight of fat.
Anyone can increase his or her daily
energy use by exercise:
Light
activities
burn 120 to 150 calories per hour
(sitting, standing, slowly moving).
Light
to moderate activities
burn 150 to 300 calories per hour
(gardening, washing a car, walking 1 to 3
miles per hour).
Heavier activities
burn 300 to 400 calories per hour
(walking faster, dancing, heavier yard work).
More
intense activities
burn 400 to 600 calories per hour
(power walking, weight lifting, climbing,
shoveling snow)
So
even though basal metabolic rate contributes so much to energy use,
an active
lifestyle can have a tremendous impact! Here’s an example:
A
person who lives a sedentary lifestyle spending
most of the working day sitting
or engaging in activities
described as “light” (as above) uses only 20% more
energy
than her basal metabolic rate.
A person who does “heavy” work for a
living uses up 50% more
energy than her basal metabolic rate.
This adds up
to an additional 500 calories per day for a 130-pound woman.
(Note: 3500
calories equals one pound).
So now you know why . . .
it’s better to burn fat than to starve fat!
And the best ways to burn fat are
through exercise and
improving your muscle-to-fat ratio (body composition).