Exercise and Weight Control
everybody seems to be interested in weight control. Some of us weigh
just the right amount, others need to gain a few pounds. Most of us
"battle the bulge" at some time in our life. Whatever our goals, we
should understand and take advantage of the important role of exercise
in keeping our weight under control.
around too much body fat is a major nuisance. Yet excess body fat is
common in modern-day living. Few of today's occupations require
vigorous physical activity, and much of our leisure time is spent in
estimates indicate that 34 million adults are considered obese (20
percent above desirable weight). Also, there has been an increase in
body fat levels in children and youth over the past 20 years. After
infancy and early childhood, the earlier the onset of obesity, the
greater the likelihood of remaining obese.
fat has been linked to such health problems as coronary heart disease,
high blood pressure, osteoporosis, diabetes, arthritis and certain
forms of cancer. Some evidence now exists showing thatobesity has a
negative effect on both health and longevity.
associated with the loss of body fat in both obese and normal weight
persons. A regular program of exercise is an important component of any
plan to help individuals lose, gain or maintain their weight.
Overweight or Overfat?
and overfat do not always mean the same thing. Some people are quite
muscular and weigh more than the average for their age and height.
However, their body composition, the amount of fat versus lean body
mass (muscle, bone, organs and tissue), is within a desirable range.
This is true for many athletes. Others weigh an average amount yet
carry around too much fat. In our society, however, overweight often
implies overfat because excess weight is commonly distributed as excess
fat. The addition of exercise to a weight control program helps control
both body weight and body fat levels.
amount of body fat is necessary for everyone. Experts say that percent
body fat for women should be about 20 percent, 15 percent for men.
Women with more than 30 percent fat and men with more than 25 percent
fat are considered obese.
How much of
your weight is fat can be assessed by a variety of methods including
underwater (hydrostatic) weighing, skinfold thickness measurements and
circumference measurements. Each requires a specially trained person to
administer the test and perform the correct calculations.
numbers obtained, a body fat percentage is determined. Assessing body
composition has an advantage over the standard height-weight tables
because it can help distinguish between "overweight" and "overfat."
self-test you can do is to pinch the thickness of the fat folds at your
waist and abdomen. If you can pinch an inch or more of fat (make sure
no muscle is included) chances are you have too much body fat.
exercise appropriately increase lean body mass while decreasing their
overall fat level. Depending on the amount of fat loss, this can result
in a loss of inches without a loss of weight, since muscle weighs more
than fat. However, with the proper combination of diet and exercise,
both body fat and overall weight can be reduced.
Energy Balance: A Weighty Concept
weight, gaining weight or maintaining your weight depends on the amount
of calories you take in and use up during the day, otherwise referred
to as energy balance. Learning how to balance energy intake (calories
in food) with energy output (calories expended through physical
activity) will help you achieve your desired weight.
underlying causes and the treatments of obesity are complex, the
concept of energy balance is relatively simple. If you eat more
calories than your body needs to perform your day's activities, the
extra calories are stored as fat. If you do not take in enough calories
to meet your body's energy needs, your body will go to the stored fat
to make up the difference. (Exercise helps ensure that stored fat,
rather than muscle tissue, is used to meet your energy needs.) If you
eat just about the same amount of calories to meet your body's energy
needs, your weight will stay the same.
average, a person consumes between 800,000 and 900,000 calories each
year! An active person needs more calories than a sedentary person, as
physically active people require energy above and beyond the day's
basic needs. All too often, people who want to lose weight concentrate
on counting calorie intake while neglecting calorie output.
powerful formula is the combination of dietary modification with
exercise. By increasing your daily physical activity and decreasing
your caloric input you can lose excess weight in the most efficient and
Each pound of
fat your body stores represents 3,500 calories of unused energy. In
order to lose one pound, you would have to create a calorie deficit of
3,500 calories by either taking in 3,500 less caloriesover a period of
time than you need or doing 3,500 calories worth of exercise. It is
recommended that no more than two pounds (7,000 calories) be lost per
week for lasting weight loss.
minutes of moderate exercise, say walking one mile, to your daily
schedule will use up 100 extra calories per day. (Your body uses
approximately 100 calories of energy to walk one mile, depending on
your body weight.) Maintaining this schedule would result in an extra
700 calories per week used up, or a loss of about 10 pounds in one
year, assuming your food intake stays the same. To look at energy
balance another way, just one extra slice of bread or one extra soft
drink a day - or any other food that contains approximately 100
calories - can add up to ten extra pounds in a year if the amount of
physical activity you do does not increase.
already have a lean figure and want to keep it you should exercise
regularly and eat a balanced diet that provides enough calories to make
up for the energy you expend. If you wish to gain weight you should
exercise regularly and increase the number of calories you consume
until you reach your desired weight. Exercise will help ensure that the
weight you gain will be lean muscle mass, not extra fat.
The Diet Connection
diet should be part of any weight control plan. A diet high in complex
carbohydrates and moderate in protein and fat will complement an
exercise program. It should include enough calories to satisfy your
daily nutrient requirements and include the proper number of servings
per day from the "basic four food groups": vegetables and fruits (4
servings), breads and cereals (4 servings), milk and milk products (2 -
4 depending on age) and meats and fish (2).
recommend that your daily intake not fall below 1200 calories unless
you are under a doctor's supervision. Also, weekly weight loss should
not exceed two pounds.
claims have been made for a variety of "crash" diets and diet pills.
And some of these very restricted diets do result in noticeable weight
loss in a short time. Much of this loss is water and such a loss is
quickly regained when normal food and liquid intake is resumed. These
diet plans are often expensive and may be dangerous.
they do not emphasize lifestyle changes that will help you maintain
your desired weight. Dieting alone will result in a loss of valuable
body tissue such as muscle mass in addition to a loss in fat.
How Many Calories
for number of calories (energy) used during a physical activity are
based on experiments that measure the amount of oxygen consumed during
a specific bout of exercise for a certain body weight.
costs of activities that require you to move your own body weight, such
as walking or jogging, are greater for heavier people since they have
more weight to move. For example, a person weighing 150 pounds would
use more calories jogging one mile than a person jogging alongside who
weighs 115 pounds. Always check to see what body weight is referred to
in caloric expenditure charts you use.
Energy Expenditure Chart
A. Sedentary Activities
Energy Costs Cals/Hour*
Lying down or sleeping
Sitting and writing, card playing, etc.
B. Moderate Activities
Bicycling (5 mph)
Canoeing (2.5 mph)
Golf (2-some, carrying clubs)
Horseback riding (sitting to trot)
Light housework, cleaning, etc.
Swimming (crawl, 20 yards/min)
Tennis (recreational doubles)
Walking (2 mph)
C. Vigorous Activities
More than 350
Bicycling (13 mph)
Circuit weight training
Football (touch, vigorous)
Ice Skating (9 mph)
Roller Skating (9 mph)
Jogging (10 minute mile, 6 mph)
Swimming (crawl, 45 yards/min)
Tennis (recreational singles)
X-country Skiing ( 5 mph)
*Hourly estimates based on values calculated for calories burned per minute for a 150 pound (68 kg) person.
*Sources: "William D. McArdle, Frank I. Katch, Victor L. Katch, "Exercise Physiology: Energy, Nutrition and Human Performance" (2nd edition), Lea & Febiger, Philadelphia, 1986; Melvin H. Williams, "Nutrition for Fitness and Sport," William C. Brown Company Publishers, Dubuque, 1983.
Exercise and Modern Living
One thing is
certain. Most people do not get enough exercise in their ordinary
routines. All of the advances of modern technology - from electric can
openers to power steering - have made life easier, more comfortable and
much less physically demanding. Yet our bodies need activity,
especially if they are carrying around too much fat. Satisfying this
need requires a definite plan, and a commitment. There are two main
ways to increase the number of calories you expend:
The best way
to control your weight is a combination of the above. The sum total of
calories used over time will help regulate your weight as well as keep
you physically fit.
looking at what kind of regular exercise program is best, let's look at
how you can increase the amount of physical activity in your daily
routine to supplement your exercise program.
pursuits such as gardening on weekends, bowling in the office league,
family outings, an evening of social dancing, and many other activities
provide added exercise. They are fun and can be considered an extra
bonus in your weight control campaign.
- Add more
"action" to your day. Walk to the neighborhood grocery store instead of
using the car. Parkseveral blocks from the office and walk the rest of
the way. Walk up the stairs instead of using the elevator; start with
one flight of steps and gradually increase.
your attitude toward movement. Instead of considering an extra little
walk or trip to the files an annoyance, look upon it as an added
fitness boost. Look for opportunities to use your body. Bend, stretch,
reach, move, lift and carry. Time-saving devices and gadgets eliminate
drudgery and are a bonus to mankind, but when they substitute too often
for physical activity they can demand a high cost in health, vigor and
bits of action are cumulative in their effects. Alone, each does not
burn a huge amount of calories. But when added together they can result
in a sizable amount of energy used over the course of the day. And they
will help improve your muscle tone and flexibility at the same time.
What Kind of Exercise?
kind of physical movement requires energy (calories), the type of
exercise that uses the most energy is aerobic exercise. The term
"aerobic" is derived from the Greek word meaning "with oxygen."
Jogging, brisk walking, swimming, biking, cross-country skiing and
aerobic dancing are some popular forms of aerobic exercise.
exercises use the body's large muscle groups in continuous, rhythmic,
sustained movement and require oxygen for the production of energy.
When oxygen is combined with food (which can come from stored fat)
energy is produced to power the body's musculature. The longer you move
aerobically, the more energy needed and the more calories used. Regular
aerobic exercise will improve your cardiorespiratory endurance, the
ability of your heart, lungs, blood vessels and associated tissues to
use oxygen to produce energy needed for activity. You'll build a
healthier body while getting rid of excess body fat.
to the aerobic exercise, supplement your program with muscle
strengthening and stretching exercises. The stronger your muscles, the
longer you will be able to keep going during aerobic activity, and the
less chance of injury.
How Much? How Often?
recommend that you do some form of aerobic exercise at least three
times a week for a minimum of 20 continuous minutes. Of course, if that
is too much, start with a shorter time span and gradually build up to
the minimum. Then gradually progress until you are able to work
aerobically for 20-40 minutes. If you need to lose a large amount of
weight, you may want to do your aerobic workout five times a week.
important to exercise at an intensity vigorous enough to cause your
heart rate and breathing to increase. How hard you should exercise
depends to a certain degree on your age, and is determined by measuring
your heart rate in beats per minute.
rate you should maintain is called your target heart rate, and there
are several ways you can arrive at this figure. The simplest is to
subtract your age from 220 and then calculate 60 to 80 percent of that
figure. Beginners should maintain the 60 percent level, more advanced
can work up to the 80 percent level. This is just a guide however, and
people with any medical limitations should discuss this formula with
You can do
different types of aerobic activities, say walking one day, riding a
bike the next. Make sure you choose an activity that can be done
regularly, and is enjoyable for you. The important thing to remember is
not to skip too many days between workouts or fitness benefits will be
lost. If you must lose a few days, gradually work back into your
The Benefits of Exercise in a Weight Control Program
of exercise are many, from producing physically fit bodies to providing
an outlet for fun and socialization. When added to a weight control
program these benefits take on increased significance.
have noted that proper exercise can help control weight by burning
excess body fat. It also has two other body-trimming advantages 1)
exercise builds muscle tissue and muscle uses calories up ata faster
rate than body fat; and 2) exercise helps reduce inches and a firm,
lean body looks slimmer even if your weight remains the same.
does not "turn into" muscle, as is often believed. Fat and muscle are
two entirely different substances and one cannot become the other.
However, muscle does use calories at a faster rate than fat which
directly affects your body's metabolic rate or energy requirement. Your
basal metabolic rate (BMR) is the amount of energy required to sustain
the body's functions at rest and it depends on your age, sex, body
size, genes and body composition. People with high levels of muscle
tend to have higher BMRs and use more calories in the resting stage.
have even shown that your metabolic rate stays elevated for some time
after vigorous exercise, causing you to use even more calories
throughout your day. Additional benefits may be seen in how exercise
affects appetite. A lean person in good shape may eat more following
increased activity, but the regular exercise will burn up the extra
calories consumed. On the other hand, vigorous exercise has been
reported to suppress appetite. And, physical activity can be used as a
positive substitute for between meal snacking.
Better Mental Health
psychological benefits of exercise are equally important to the weight
conscious person. Exercise decreases stress and relieves tensions that
might otherwise lead to overeating. Exercise builds physical fitness
which in turn builds self-confidence, enhanced self-image, and a
positive outlook. When you start to feel good about yourself, you are
more likely to want to make other positive changes in your lifestyle
that will help keep your weight under control.
exercise can be fun, provide recreation and offer opportunities for
companionship. The exhilaration and emotional release of participating
in sports or other activities are a boost to mental and physical
health. Pent-up anxieties and frustrations seem to disappear when
you're concentrating on returning a serve, sinking a putt or going that
Tips to Get You Started
you are now convinced that to successfully manage your weight you must
include exercise in your daily routine. Here are some tips to get you
1. Check with
your doctor first. Since you are carrying around some extra "baggage,"
it is wise to get your doctor's "OK" before embarking on an exercise
activities that you think you'll enjoy. Most people will stick to their
exercise program if they are having fun, even though they are working
aside a regular exercise time. Whether this means joining an exercise
class or getting up a little earlier every day, make time for this
addition to your routine and don't let anything get in your way.
Planning ahead will help you get around interruptions in your workout
schedule, such as bad weather and vacations.
short term goals. Don't expect to lose 20 pounds in two weeks. It has
taken awhile for you to gain the weight, it will take time to lose it.
Keep a record of your progress and tell your friends and family about
your exercise program. Change exercises or invite friends to join you
to make your workout more enjoyable. There is no "best" exercise - just
the one that works best for you. It won't be easy, especially at the
start. But as you begin to feel better, look better and enjoy a new
zest for life, you will be rewarded many times over for your efforts.
Tips to Keep You Going
1. Adopt a specific plan and write it down.
2. Keep setting realistic goals as you go along, and remind yourself of them often.
3. Keep a log to record your progress and make sure to keep it up-to-date.
4. Include weight and/or percent body fat measures in your log. Extra pounds can easily creep back.
5. Upgrade your fitness program as you progress.
6. Enlist the support and company of your family and friends.
7. Update others on your successes.
8. Avoid injuries by pacing yourself and including a warmup and cool down period as part of every workout.
9. Reward yourself periodically for a job well done!
Source: The President's Council on Physical Fitness and Sports