If a cookie contains 100 calories, anyone who eats it
consumes 100 calories.
But the other side of the energy equation isn't that simple.
When it comes to burning off calories, people who do the same
activity at the same pace for the same amount of time can
burn vastly different numbers of calories, depending on their
Larger vs. Smaller
For example, if a family of three jogs side-by-side for 30
minutes, the 175-pound father will burn 400 calories, the 130-
pound mother will burn 300 calories and the 65-pound child
will burn 180 calories.
Larger people burn more calories than smaller people,
particularly with activities like walking or stair climbing
where they have to carry their own weight.
Exercisers are often misled by workout equipment or charts
that don't factor in weight, when they proclaim how many
calories are being burned by an activity.
If an exercise machine or chart calculates the calories
burned by an "average" 150-pound person, the results would be
"vastly inaccurate" for much larger or smaller exercisers.
Avoid The "Death Grip"
In addition, leaning on the hand rails of a stair climber or
keeping a "death grip" on the treadmill railing will greatly
decrease caloric expenditure.
The machine is assuming that your legs are carrying your
entire body weight. But if you're supporting yourself on the
handles, you're actually burning about 20 to 30 percent fewer
calories than the machine indicates.
Know What You're Burning
Knowing how many calories you're burning during activity can
be important if you're trying to lose weight, since the
general rule of thumb for weight loss is to create a 300- to
500-calorie deficit each day. This means consuming 300 to 500
fewer calories than you expend.
Half of this calorie deficit should come from eating less and
half should come from exercising more. We generally advise
people who want to lose weight to expend at least 250
calories more each day than they have in the past.
Additionally, they should eat 250 fewer calories than they've
It's important to eat enough to fuel your body, and we also
warn men not to eat less than 1,200 calories per day and
women not to eat less than 1,000. That's because severely
restricting calories prompts the body to try to conserve fat
stores, so it breaks down lean tissue mass, robbing the body
of muscle and bone.
People who are overweight want to lose fat. But many don't
realize that about half of the weight lost on extremely low-
calorie diets isn't from fat, it's from lean tissue.
(C) 2004 Dr. Reuven Bruner. All Rights Reserved.
Contact Dr. Bruner at: POB 1903, Jerusalem, 91314, Israel;
Tel: (02) 652-7684; Mobile: 052 865-821; Fax: (02) 652-7227;