Exercise and
Weight Control
Contents
Weight-The Ongoing Battle
Just about
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.
Carrying 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 sedentary pursuits.
Recent 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.
Excess body 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 that obesity has a
negative effect on both health and longevity.
Exercise is
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?
Overweight 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.
A certain 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.
From the 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."
An easy 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.
People who
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
Losing 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.
Although the
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.
On the 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. The most 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 healthful way.
Counting Calories
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 calories over 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.
Adding 15 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.
lf you 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
A balanced 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).
Experts 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.
Remarkable 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. Moreover,
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
The estimates 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.
The energy 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 |
|
90 |
|
Sitting quietly |
|
84 |
Sitting and writing, card
playing, etc. |
|
114 |
|
B. Moderate Activities |
(150-350) |
|
Bicycling (5 mph) |
|
174 |
|
Canoeing (2.5 mph) |
|
174 |
|
Dancing (Ballroom) |
|
210 |
|
Golf (2-some, carrying clubs)
|
|
324 |
|
Horseback riding (sitting to trot) |
|
246 |
|
Light housework, cleaning, etc. |
|
246 |
|
Swimming (crawl, 20 yards/min) |
|
288 |
|
Tennis (recreational doubles)
|
|
312 |
|
Volleyball (recreational) |
|
264 |
|
Walking (2 mph) |
|
198 |
|
C. Vigorous Activities |
More than 350 |
|
Aerobic Dancing |
|
546 |
|
Basketball (recreational)
|
|
450 |
|
Bicycling (13 mph) |
|
612 |
|
Circuit weight training
|
|
756 |
|
Football (touch, vigorous) |
|
498 |
|
Ice Skating (9 mph) |
|
384 |
|
Racquetball |
|
588 |
|
Roller Skating (9 mph) |
|
384 |
|
Jogging (10 minute mile, 6 mph)
|
|
654 |
|
Scrubbing Floors |
|
440 |
|
Swimming (crawl, 45 yards/min) |
|
522 |
|
Tennis (recreational singles) |
|
450 |
|
X-country Skiing ( 5 mph) |
|
690 |
*Hourly
estimates based on values calculated for calories burned per minute
for a 150 pound (68 kg) person.
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:
- Start a regular
exercise program if you do not have one already.
- Increase the
amount of physical activity in your daily routine.
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.
Active Lifestyles
Before 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.
- Recreational
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. Park several 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.
- Change 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 fitness.
These little 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?
Although any 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.
Aerobic 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.
In addition 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?
Experts 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.
It is 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.
The heart 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 their physician.
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 routine.
The
Benefits of Exercise in a Weight Control Program
The benefits 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.
We already 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 at a 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.
Remember, fat 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.
Some studies 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
The 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.
In addition,
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 extra mile.
Tips to Get You Started
Hopefully, you are
now convinced that in order to successfully manage your weight you
must include exercise in your daily routine. Here are some tips to
get you started:
- 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 program.
- Choose
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 hard.
- Set 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.
- Set 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 achievements.
- Vary 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
- Adopt a
specific plan and write it down.
- Keep setting
realistic goals as you go along, and remind yourself of them
often.
- Keep a log to
record your progress and make sure to keep it up-to-date.
- Include weight
and/or percent body fat measures in your log. Extra pounds can
easily creep back.
- Upgrade your
fitness program as you progress.
- Enlist the
support and company of your family and friends.
- Update others
on your successes.
- Avoid injuries
by pacing yourself and including a warm-up and cool down period as
part of every workout.
- Reward
yourself periodically for a job well done!
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