C H A P T E R 1 5
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Lecture Outline
I. Types of Physical Activity
Nearly all types of physical activity can be grouped under one of five basic kinds of
exercise. Each of these types can contribute to strength, flexibility, speed, or physical fitness, but
aerobic exercise is especially important for cardiovascular health.
II. Reasons for Exercising
People exercise for a number of reasons, including physical fitness, weight control, and
cardiovascular fitness.
A. Physical Fitness
Fitness can be considered as either organic or dynamic. Organic fitness refers to inherited
characteristics whereas dynamic fitness is determined by the amount and kinds of exercise a
person performs. This chapter considers only dynamic, which can be changed through
activity. Physical fitness has at least four benefits: muscle strength, muscle endurance,
flexibility, and cardiorespiratory or aerobic fitness. Each of the five types of exercise can
contribute to these four types of benefits, but no one type fulfills all requirements.
1. Muscle Strength and Endurance
Muscle strength is a measure of how strongly a muscle can contract. Muscle
2. Flexibility
Flexibility is the range of motion that a joint can attain. It is specific to each joint, so
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3. Aerobic Fitness
Aerobic exercise increases the body’s requirement for oxygen, thereby causing the
respiratory system to work harder and the heart to pump blood at a higher rate. Exercise
and increase the efficiency of the cardiovascular system.
B. Weight Control
Physical activity combined with diet is an excellent way to lose weight, but exercise
alone is sufficient to lower the ratio of fat tissue to muscle tissue and thus improve body
composition. Dieters tend to lose both fat and muscle tissue, but aerobic exercisers lose only
fat tissue and retain lean muscle. Long duration, high intensity exercise is necessary to
produce weight loss without a change in eating, but physical activity also raises metabolic
rate. This change can be important for weight loss.
III. Physical Activity and Cardiovascular Health
More important than physical fitness or weight control is the issue of exercise and
cardiovascular health.
A. Early Studies
During the early 1950s, several studies found that sedentary workers were more prone to
heart disease than more active workers. None of these early studies, however, controlled for
B. Later Studies
Studies during the past 25 years generally have avoided some of the flaws of earlier
studies, demonstrating not only a consistent relationship between physical activity and
decreased CVD but also a consistent dose-response relationship between physical activity
and several measures of health, including heart disease, stroke, and all-cause mortality.
People who are active may benefit from increasing their activity level, but the largest benefit
applies to sedentary people who become active.
C. Do Women and Men Benefit Equally?
Middle-aged and older women benefit from a regular physical activity program. Moderate
and vigorous activity four or five times a week yield protection against CVD and all-cause
mortality. A summary of the evidence reveals that women and men are protected about
equally by regular physical activity.
D. Physical Activity and Cholesterol Levels
Research indicates that aerobic exercise can raise HDL levels without raising LDL levels,
resulting in a more favorable ratio of total cholesterol to HDL and a possible protection
against heart disease. Moderate exercise may lower LDL and triglycerides but the findings
are more consistent concerning raising HDL levels. These benefits of exercise for cholesterol
apply to children, adolescents, young and middle-aged men and women.
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IV. Other Health Benefits of Physical Activity
Physical activity may also help prevent some kinds of cancer, protect against loss of bone
density, control diabetes, and confer psychological benefits.
A. Protection against Cancer
Physical activity helps protect against colon and breast cancer and possibly also cancer of
the edomentrium, lung, and prostate. Exercise may also benefit individuals with cancer,
helping them to manage some of the distressing side effects of treatment.
1. Decreased Depression
People who exercise regularly are generally less depressed than those who do not.
Aerobic exercise is more effective than no treatment, and physical activity may be
comparable to cognitive therapy or antidepressant drugs. These effects make physical
activity an attractive candidate for addition to programs to control depression.
2. Reduced Anxiety
Exercise is less effective in reducing trait anxiety—a more or less constant
3. Buffer against Stress
Physical activity can relieve people from stress, but the evidence that it can buffer
4. Better Cognitive Functioning
People who exercise regularly show greater attention, processing speed, memory, and
executive functioning than adults who do not participate in regular physical exercise.
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V. Hazards of Physical Activity
Physical activity is also associated with some potential dangers such as overtraining to the
point of staleness, but dependency, injury, and even death are possible consequences.
A. Exercise Addiction
Some people show characteristics of dependency on physical activity, such as showing a
B. Injuries from Physical Activity
The nature of exercise-related injuries varies with type of activity. Injury is more
common among infrequent exercisers, and those who begin a strenuous exercise program
may be at risk if they exercise without a medical examination or supervision. Regular
exercisers are also at risk for a variety of injuries; musculoskeletal injury is the most
common.
C. Death during Exercise
Death during exercise is rare. Most exercise deaths occur during or immediately after
vigorous activity. Nearly all exercise-related deaths are the results of heart attack and are
attributable to preexisting conditions, making a stress test a wise precaution for older, unfit,
sedentary people who want to begin an exercise program.
D. Reducing Exercise Injuries
VI. How Much Is Enough but Not Too Much?
In general, any amount of physical activity is better than none, and the type of activity can
VII. Improving Adherence to Physical Activity
Only 33% of adults are meeting physical activity guidelines.
A. Informational Interventions
Informational interventions seek to raise awareness of the important of physical
activity and its benefits. Informational interventions can be mass media campaigns or
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largely successful at behavior change. Individually tailored health behavior change
programs, on the other hand, are not as successful at maintaining health behavior
change.
C. Environmental Interventions
Environmental Interventions are interventions that seek to change the physical
environment—such as building sidewalks or parks—to promote physical exercise in
people.
Exploring Health on the Web
Exercise and physical fitness on the Internet are usually tied to a specific sport or recreational
activity or to a condition for which exercise is recommended. Some sites provide information
about the benefits of physical fitness or give advice about increasing fitness to achieve better
health.
HealthInsite is a website maintained by the Australian government, and it contains
resources on exercise, fitness, and sports and access to other sites and information.
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The National Coalition for Promoting Physical Activity website provides information on
public policy but also contains multiple links and resources related to physical activity.
Suggested Activities
Personal Health Profile—Examining Activity Level
As this chapter suggests, regular exercise should be an important part of any healthy
lifestyle. For their Personal Health Profile, your students should examine their present level of
physical activity and compare it to the optimal level suggested by current research. Are they
exercising too little? Too much? Are they relying on the wrong type of exercise? Do their
exercise habits make them susceptible to injuries? What benefits can they expect from exercise?
Once again, they should cite original research and not rely on secondary sources or hearsay to
evaluate the benefits and risks of their exercise activities.
Never Too Late or Too Early to Exercise
As the “Would You Believe. . . ?” box in Chapter 15 discusses, it is never too late or too
early to become involved in physical activity. In addition, benefits accrue to individuals at any
developmental period. However, the types of activities that are safe and appropriate vary with
age.
Your students can compile exercise guidelines and understand the benefits for people in
various age groups by consulting print and online sources to find the benefits and hazards of
exercise. This compilation of information will allow your students to understand what benefits
are most important at which developmental periods and also to compile age-appropriate safety
guidelines for physical activity.
Debate: Can Exercise Be an Addiction?
One of the hazards of exercise occurs when people exercise to the point of neglecting
other aspects of their lives and when they exercise despite injuries. These behaviors are
sometimes interpreted as exercise addiction, but applying the concept of addiction to exercise is
controversial. This controversy can become a class debate.
Arrange a debate in which one side promotes the position that exercise addiction is
equivalent to drug addiction, whereas the other side argues that there are too many differences
between people use abuse drugs and those who exercise a great deal. Those students who are on
the team arguing against exercise addiction may want to emphasize the health benefits of
physical activity, whereas those on the other side should emphasize the hazards and the
compulsive nature of obligatory exercise.
Opinion Poll
Most of us have a tendency to use our own behavior and lifestyle as a standard for
judging what others should do. We believe that our health habits are the proper ones. If we
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opinion about the type and amount of exercise the average adult should receive to maintain or
enhance health (not to control weight or get into shape to play a sport), your students should then
ask participants about the type and amount of exercise they receive. The data can be analyzed for
relationship between the two amounts of exercise or the differences among respondents in
various demographic categories.
Understanding Child’s Play
Since the 1970s, the physical activity and physical fitness levels of school-aged children
in the United States have declined, and children now spend a large amount of their time in
sedentary activities. To better understand these trends, arrange a panel discussion among children
about their physical activities. Many adult authorities have discussed this trend and measured
fitness and activity levels, but your students might benefit from the children’s point of view.
Try to get children who are old enough to discuss what they do for fun. Children between
ages 10 and 16 years might be a good age range. Be sure to include both boys and girls, because
gender differences in physical activity levels exist as early as elementary school and that these
differences continue to grow with age.
Encourage the children to talk about what they do for fun, what is the most fun, where
they play, with whom they play, how often their play includes physical activity, and how they
feel about different types of physical activities. Ask them about the physical education program
in their schools—what types of activities they do, whether or not the programs include activities
for those kids who are not talented athletes, how often their P.E. classes include vigorous
exercise, and how they feel about their school’s program.
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Video Recommendations
From Films for the Humanities & Sciences:
Keeping Fit (1998) is a 29-minute program that details the dangers of a sedentary lifestyle and
explains the types of fitness.
Healthy Habits = Healthy Children (2001) emphasizes the role of physical activity in preventing
childhood obesity and in overall health for a lifetime.
How to Live Longer…Better explores the connections between physical activity and other healthy
habits and life extension.
Videos from the Web:
Multiple Choice Questions
1. Isometric exercise is designed to
a. increase cardiovascular fitness.
b. increase lung capacity.
c. increase muscle endurance.
d. increase muscle strength.
2. The type of exercise that requires the LEAST amount of physical activity is
a. isometric.
b. isotonic.
c. isokinetic.
d. anaerobic.
3. Brooke is bedridden after an auto accident. What exercise would help her maintain
muscular strength in her arms with a minimum of movement?
a. isometric
b. isotonic
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c. aerobic
d. isokinetic
4. Pushing muscles hard against an immovable object is an example of _____ exercise.
a. aerobic
b. anaerobic
c. isokinetic
d. isometric
5. Isotonic exercise is designed to
a. increase cardiovascular fitness.
b. increase lung capacity.
c. increase muscle endurance.
d. increase muscle strength.
6. What type of exercise requires specialized equipment to promote muscle strength and
muscle endurance?
a. isokinetic
b. isotonic
c. isometric
d. anaerobic
7. What distinguishes anaerobic exercise from aerobic exercise?
a. the amount of muscle contraction
b. the amount of oxygen consumption
c. the degree of joint rotation
d. the amount of body movement
8. Willa is a track star in college. Her specialties are the 100-meter dash and the 200-meter
dash. The type of exercise she is receiving during these races is mostly
a. isometric.
b. isotonic.
c. isokinetic.
d. anaerobic.
9. Organic fitness is determined by
a. inherent characteristics of the body.
b. the exercise stress test.
c. regular strenuous exercise.
d. degree of muscle strength.
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10. Tatum was considered a natural athlete in college, but she has not been active since she
left college 10 years ago. Presently, the type of fitness that Tatum probably has is
a. dynamic fitness.
b. organic fitness.
c. both dynamic and organic fitness.
d. neither dynamic nor organic fitness.
11. The type of fitness known as flexibility is best increased by
a. weight lifting.
b. stretching.
c. jogging.
d. short, fast runs.
12. Cynthia injured her knee while downhill skiing and is currently in a rehab program to
help regain strength and flexibility in her knee. She is most likely doing ________
exercise.
a. anaerobic
b. aerobic
c. isometric
d. isokinetic
13. Activities such as jogging, cross-country skiing, or swimming are classified as
_________ exercise and activities such as short-distance running or softball are classified
as _________ exercise.
a. anaerobic; aerobic
b. isometric; aerobic
c. aerobic; anaerobic
d. aerobic; isometric
14. If the goal of your exercise program is to improve your cardiovascular health, you should
most likely engage in ________ exercise.
a. anaerobic
b. aerobic
c. isometric
d. isokinetic
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15. Aerobic fitness gained through vigorous physical activity
a. decreases the risk of heart attack.
b. decreases cardiorespiratory fitness.
c. increases resting heart rate.
d. decreases exercise-related injuries.
16. Aerobic fitness tends to
a. increase muscle strength.
b. decrease resting heart rate.
c. decrease resting blood pressure.
d. both b and c
17. People who have high aerobic fitness, compared with those who have low aerobic fitness,
a. have about the same rate of all-cause mortality.
b. have a higher rate of all-cause mortality.
c. have a lower death rate from heart disease.
d. have a higher death rate from heart disease.
18. Bess has moderate weight and good organic fitness. If she begins an aerobic exercise
program, she will probably
a. lose 10 to 15 pound.
b. gain 10 to 15 pounds.
c. increase lean body weight and decrease body fat.
d. decrease lean body weight and increase body fat.
19. With regard to diet, exercise, and weight loss, which statement is true?
a. Exercise alone can produce weight loss.
b. Dieters lose weight, but they also retain lean muscle tissue.
c. Exercisers lose weight, but they lose mostly lean muscle tissue.
d. Both a and b are true.
20. Lynn would like to quit smoking, but she is concerned that she will gain weight. What
advice would you give her?
a. Keep smoking, because some people who quit gain as many as 40 or 50 pounds.
b. Quit smoking, but begin a 1,000 calorie a day diet.
c. Quit smoking, eat regularly, and begin a regular physical activity program.
d. Quit smoking but begin a very low calorie diet and a physical activity program.
21. Muscle _______ is a measure of how strongly a muscle can contract.
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a. strength
b. endurance
c. flexibility
d. fitness
22. Exercise like yoga and tai chi can help provide muscle ___________.
a. strength
b. endurance
c. flexibility
d. fitness
23. Tara is relatively satisfied with the looks of her upper body, but she wants to lose weight
on her hips while retaining the rest of her body composition. Tara should
a. understand that exercise will not accomplish spot reduction.
b. begin an aerobic exercise program.
c. use isometric exercises.
d. use isokinetic exercises.
24. People may lose weight through exercise alone if they
a. engage in vigorous physical activity about an hour a day.
b. combine isometric exercise with isokinetic exercise.
c. run short distances at a fast speed.
d. combine isokinetic exercise with isotonic exercise.
25. Joel, a 15-year-old high school sophomore, sits in front of his computer eating “junk
food” almost constantly when he is not sleeping or in school. How can Joel’s behavior
affect his weight?
a. His inactivity is positively related to weight gain.
b. His high caloric intake is positively related to weight gain.
c. His eating increases his metabolic rate, which is related to weight loss.
d. Both a and b are factors.
26. The emphasis on exercise as a factor in weight control programs has come about because
of research that found that
a. exercise elevates metabolism.
b. exercise burns more calories than was previously believed.
c. exercise acts differently on the muscle tissue of obese people.
d. isometric exercise is the most advantageous type.
27. Research has found that people who experienced the greatest benefits from physical
activity were
a. those who changed from a sedentary to an active lifestyle.
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b. those who changed from an active to a more active lifestyle.
c. women.
d. children.
28. Clinton was a long distance runner in high school and college. Now, at age 30, he lives an
inactive life. Clinton believes that his earlier experiences as a track star will offer
permanent protection against cardiovascular disease. Clinton’s
a. belief is correct.
b. belief is incorrect.
c. future risk of CVD will be about 50% lower compared to men his age who have
never exercised.
d. future risk of CVD will be higher than men of his age who have never exercised.
29. Women who exercise
a. have about the same rate of all-cause mortality as do men who exercise.
b. have a lower risk of all-cause mortality than do men who exercise.
c. have a higher risk of all-cause mortality than do men who exercise.
d. have about the same risk of all-cause mortality as do men, but their rate of lung
cancer is much higher than that of men who exercise.
30. Research on the effects of physical activity has generally found that a program of regular
physical activity
a. can add as much as two years to people’s lives.
b. can lower levels of disability during old age.
c. both a and b
d. results in more deaths than an inactive lifestyle.
31. The benefits of physical activity are most strongly evident with
a. heart disease.
b. injuries.
c. cancer.
d. young children.
32. Research indicates that exercise protects against heart disease by
a. raising high-density lipoprotein cholesterol.
b. raising total cholesterol.
c. lowering total cholesterol.
d. lowering high-density lipoprotein cholesterol.