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Physical Activity And Weight Control Essay, Research Paper
Regular physical activity is an important part of effective weight loss and weight maintenance. It also
can help prevent several diseases and improve your overall health. It does not matter what type of
physical activity you perform–sports, planned exercise, household chores, yard work, or work-related
tasks–all are beneficial. Studies show that even the most inactive people can gain significant health
benefits if they accumulate 30 minutes or more of physical activity per day. Based on these findings,
the U.S. Public Health Service has identified increased physical activity as a priority in Healthy People
2000, our national objectives to improve the health of Americans by the year 2000.
Research consistently shows that regular physical activity, combined with healthy eating habits, is the
most efficient and healthful way to control your weight. Whether you are trying to lose weight or
maintain it, you should understand the important role of physical activity and include it in your
How Can Physical Activity Help Control My Weight?
Physical activity helps to control your weight by using excess calories that otherwise would be stored
as fat. Your body weight is regulated by the number of calories you eat and use each day. Everything
you eat contains calories, and everything you do uses calories, including sleeping, breathing, and
digesting food. Any physical activity in addition to what you normally do will use extra calories.
Balancing the calories you use through physical activity with the calories you eat will help you achieve
your desired weight. When you eat more calories than you need to perform your day’s activities, your
body stores the extra calories and you gain weight (a). When you eat fewer calories than you use, your
body uses the stored calories and you lose weight (b). When you eat the same amount of calories as
your body uses, your weight stays the same (c).
Any type of physical activity you choose to do–strenuous activities such as running or aerobic
dancing or moderate-intensity activities such as walking or household work–will increase the number
of calories your body uses. The key to successful weight control and improved overall health is
making physical activity a part of your daily routine.
What Are the Health Benefits of Physical Activity?
In addition to helping to control your weight, research shows that regular physical activity can reduce
your risk for several diseases and conditions and improve your overall quality of life. Regular physical
activity can help protect you from the following health problems.
Heart Disease and Stroke. Daily physical activity can help prevent heart disease and stroke by
strengthening your heart muscle, lowering your blood pressure, raising your high-density
lipoprotein (HDL) levels (good cholesterol) and lowering low-density lipoprotein (LDL)
levels (bad cholesterol), improving blood flow, and increasing your heart’s working capacity.
High Blood Pressure. Regular physical activity can reduce blood pressure in those with high
blood pressure levels. Physical activity also reduces body fatness, which is associated with
high blood pressure.
Noninsulin-Dependent Diabetes. By reducing body fatness, physical activity can help to
prevent and control this type of diabetes.
Obesity. Physical activity helps to reduce body fat by building or preserving muscle mass and
improving the body’s ability to use calories. When physical activity is combined with proper
nutrition, it can help control weight and prevent obesity, a major risk factor for many diseases.
Back Pain. By increasing muscle strength and endurance and improving flexibility and
posture, regular exercise helps to prevent back pain.
Osteoporosis. Regular weight-bearing exercise promotes bone formation and may prevent
many forms of bone loss associated with aging.
Studies on the psychological effects of exercise have found that regular physical activity can improve
your mood and the way you feel about yourself. Researchers also have found that exercise is likely to
reduce depression and anxiety and help you to better manage stress.
Keep these health benefits in mind when deciding whether or not to exercise. And remember, any
amount of physical activity you do is better than none at all.
How Much Should I Exercise?
For the greatest overall health benefits, experts recommend that you do 20 to 30 minutes of aerobic
activity three or more times a week and some type of muscle strengthening activity and stretching at
least twice a week. However, if you are unable to do this level of activity, you can gain substantial
health benefits by accumulating 30 minutes or more of moderate-intensity physical activity a day, at
least five times a week.
If you have been inactive for a while, you may want to start with less strenuous activities such as
walking or swimming at a comfortable pace. Beginning at a slow pace will allow you to become
physically fit without straining your body. Once you are in better shape, you can gradually do more
Moderate-intensity activities include some of the things you may already be doing during a day or
week, such as gardening and housework. These activities can be done in short spurts–10 minutes
here, 8 minutes there. Alone, each action does not have a great effect on your health, but regularly
accumulating 30 minutes of activity over the course of the day can result in substantial health benefits.
To become more active throughout your day, take advantage of any chance to get up and move
around. Here are some examples:
Take a short walk around the block
Play actively with the kids
Walk up the stairs instead of taking the elevator
Mow the lawn
Take an activity break — get up and stretch or walk around
Park your car a little farther away from your destination and walk the extra distance
The point is not to make physical activity an unwelcome chore, but to make the most of the
opportunities you have to be active.
Aerobic activity is an important addition to moderate-intensity exercise. Aerobic exercise is any
extended activity that makes you breathe hard while using the large muscle groups at a regular, even
pace. Aerobic activities help make your heart stronger and more efficient. They also use more calories
than other activities. Some examples of aerobic activities include:
Ice or roller skating
Cross-country or downhill skiing
Using aerobic equipment (i.e., treadmill, stationary bike)
To get the most health benefits from aerobic activity, you should exercise at a level strenuous enough
to raise your heart rate to your target zone. Your target heart rate zone is 50 to 75 percent of your
maximum heart rate (the fastest your heart can beat). To find your target zone, look for the category
closest to your age in the chart below and read across the line. For example, if you are 35 years old,
your target heart rate zone is 93-138 beats per minute.
Age Target Heart Rate Zone 50-75% Average Maximum Heart Rate 100%
20-30 years 98-146 beats per min. 195
31-40 years 93-138 beats per min. 185
41-50 years 88-131 beats per min. 175
51-60 years 83-123 beats per min. 165
61+ years 78-116 beats per min. 155
To see if you are exercising within your target heart rate zone, count the number of pulse beats at your
wrist or neck for 15 seconds, then multiply by four to get the beats per minute. Your heart should be
beating within your target heart rate zone. If your heart is beating faster than your target heart rate, you
are exercising too hard and should slow down. If your heart is beating slower than your target heart
rate, you should exercise a little harder.
When you begin your exercise program, aim for the lower part of your target zone (50 percent). As
you get into better shape, slowly build up to the higher part of your target zone (75 percent). If
exercising within your target zone seems too hard, exercise at a pace that is comfortable for you. You
will find that, with time, you will feel more comfortable exercising and can slowly increase to your
Stretching and Muscle Strengthening Exercises
Stretching and strengthening exercises such as weight training should also be a part of your physical
activity program. In addition to using calories, these exercises strengthen your muscles and bones and
help prevent injury.
Tips to a Safe and Successful Physical Activity Program
Make sure you are in good health. Answer the following questions* before you begin exercising.
1.Has a doctor ever said you have heart problems?
2.Do you frequently suffer from chest pains?
3.Do you often feel faint or have dizzy spells?
4.Has a doctor ever said you have high blood pressure?
5.Has a doctor ever told you that you have a bone or joint problem, such as arthritis, that has
been or could be aggravated by exercise?
6.Are you over the age of 65 and not accustomed to exercise?
7.Are you taking prescription medications, such as those for high blood pressure?
8.Is there a good medical reason, not mentioned here, why you should not exercise?
*Source: British Columbia Department of Health
If you answered “yes” to any of these questions, you should see your doctor before you begin an
Follow a gradual approach to exercise to get the most benefits with the fewest risks. If you
have not been exercising, start at a slow pace and as you become more fit, gradually increase
the amount of time and the pace of your activity.
Choose activities that you enjoy and that fit your personality. For example, if you like team
sports or group activities, choose things such as soccer or aerobics. If you prefer individual
activities, choose things such as swimming or walking. Also, plan your activities for a time of
day that suits your personality. If you are a morning person, exercise before you begin the
rest of your day’s activities. If you have more energy in the evening, plan activities that can be
done at the end of the day. You will be more likely to stick to a physical activity program if it
is convenient and enjoyable.
Exercise regularly. To gain the most health benefits it is important to exercise as regularly as
possible. Make sure you choose activities that will fit into your schedule.
Exercise at a comfortable pace. For example, while jogging or walking briskly you should be
able to hold a conversation. If you do not feel normal again within 10 minutes following
exercise, you are exercising too hard. Also, if you have difficulty breathing or feel faint or
weak during or after exercise, you are exercising too hard.
Maximize your safety and comfort. Wear shoes that fit and clothes that move with you, and
always exercise in a safe location. Many people walk in indoor shopping malls for exercise.
Malls are climate controlled and offer protection from bad weather.
Vary your activities. Choose a variety of activities so you don’t get bored with any one thing.
Encourage your family or friends to support you and join you in your activity. If you have
children, it is best to build healthy habits when they are young. When parents are active,
children are more likely to be active and stay active for the rest of their lives.
Challenge yourself. Set short-term as well as long-term goals and celebrate every success, no
matter how small.
Whether your goal is to control your weight or just to feel healthier, becoming physically active is a
step in the right direction. Take advantage of the health benefits that regular exercise can offer and
make physical activity a part of your lifestyle.
The following organizations have materials on physical activity and weight control available to the
President’s Council on Physical Fitness and Sports
701 Pennsylvania Avenue, NW
Washington, DC 20004
Phone: (202) 272-3421
National Heart, Lung, and Blood Institute
P.O. Box 30105
Bethesda, MD 20824-0105
Phone: (301) 251-1222
American College of Sports Medicine
P.O. Box 1440
Indianapolis, IN 46206-1440
Phone: (317) 637-9200
Weight-control Information Network
1 WIN WAY
BETHESDA, MD 20892-3665
Toll-free Number: (800) WIN-8098
The Weight-control Information Network (WIN) is a service of the National Institute of Diabetes and
Digestive and Kidney Diseases, part of the National Institutes of Health. Authorized by Congress
(Public Law 103-43). WIN assembles and disseminates to health professionals and the general public
information on weight control, obesity, and nutritional disorders. WIN responds to requests for
information; develops, reviews, and distributes publications; and develops communication strategies to
encourage individuals to achieve and maintain a health weight.
Publications produced by WIN are reviewed for scientific accuracy, content, and readability. Materials
produced by other sources are also reviewed for scientific accuracy and are distributed, along with
WIN publications, to answer requests.
This e-pub is not copyrighted. WIN encourages unlimited duplication and distribution of this e-text.
NIH Publication No. 96-4031