Physical Activity and Stress Resistance

Participation in regular physical activity is one of the most effective ways to increase your stress resistance. Countless studies comparing people with high and low levels of stress resistance have found exercise to be one of the most salient discriminators between these two groups (Brown, 1991; Dienstbier, 1991; Kobasa, Maddi, & Puccetti, 1982; Roth & Holmes, 1987; Sheets, Gorenflo, & Forney, 1993). An important note is that the amount and intensity of exercise required to produce stress management benefits need not be overwhelming (Berger & Owen, 1992). While many athletes enjoy extended periods of intense activity, other people find stress relief with a brisk walk, an hour of gardening, or a game of volleyball on the beach.

    Physical activity has both short and long term effects. Many people report feeling less stress both during and after a single exercise session. Regular exercise, which generally means performing some sort of physical activity at least three times a week, has a cumulative effect as well, and exercisers report feeling less stressed even on days when they don't engage in physical activity (Berger, Friedman, & Eaton, 1988; Helin & Hanninen, 1988; Holmes & Roth, 1988; Morgan, 1985).

    The health benefits of exercise read like the promises of a huckster selling snake oil: increased energy, less fatigue, better sleep, weight control, toned muscles, and even a better sex life. Regular exercise reduces your risk of many chronic diseases, including artery disease, type II diabetes, hypertension, obesity, and even some types of cancer (McGinnis, 1992). The mental health benefits of exercise go far beyond stress management. Regular physical activity has been shown to decrease both anxiety and depression and to improve mood and self-esteem (Blumenthal, et al., 1982; Brown & Harrison, 1986; Finkenberg, DiNucci, McCune, & McCune, 1993; Greist et al., 1979; Jasnoski & Holmes, 1981; Klein et al., 1985; Mellion, 1985; Morgan, 1979; Morris & Salmon, 1994; Nicoloff & Schwenk, 1995; Pierce & Pate, 1994; Pronk, Crouse, & Rohack, 1995; Raglin & Morgan, 1987; Stein & Motta, 1992; Taylor, Sallis, & Needle, 1985).

PHYSICAL ACTIVITY, EXERCISE, AND STRESS

Physical activity and exercise both refer to activities requiring movement, usually movement of a repetitive nature. We generally use the term physical activity to include all types of movement, from mowing the lawn, gardening, housekeeping, and chasing children to more structured workouts and recreational and sports activities. Exercise activities are a subset of physical activity and suggest activity performed intentionally to improve physical fitness. The main difference between the terms physical activity and exercise is the intention with which the action is performed. Physical activity happens because you need to get something done, or you are doing something you want to do, like dancing or windsurfing; exercise suggests activity performed for the sake of expending energy. The terms are often used interchangeably, however, since all physical activity can be used for exercise.

    There are countless forms of physical activity, from bowling to triathlons. Despite the sizable differences among the various types of physical activity, research has found that just about any kind of activity can help reduce stress. This is probably because exercise exerts its stress management benefits in several ways. Exercise can induce biochemical and other physiological changes that help you feel relaxed, help your muscles relax, help you recover faster from emotional stress, and provide health benefits that counterbalance the negative effects of stress. Physical activity can provide a welcome diversion from sources of stress. Some physical activities relieve boredom and provide opportunities for social interaction. By improving people's health and fitness, exercise may help them feel better generally and better about themselves. Mastering a new skill or excelling in a sport improves selfesteem. Some physical activities are even fun, and, to quote Dr. Seuss (1960), "Fun is good."

Physiological Effects: Fight, Flight, or Exercise

On an intuitive level, it certainly makes sense that exercise should help reduce our physical stress response, at least in the short run. After all, the fight-or-flight response gears us up to respond physically to stressors. The physical changes associated with the stress response are practically begging our muscles to move. While it is certainly not feasible to run right out of a stressful exam and track down your favorite tennis partner for a vigorous game or two, exercise after the fact will still allow your body to act out the fight-or-flight response.

    Research supports this intuition. Recall from Chapter 2 that stress hormones increase the level of fuel substrates such as sugar and fats in the bloodstream, so you'll have plenty of energy to fight or flee. Exercise allows the stress hormones to exert their effects in a harmless way. Although an increase in energy substrates is harmful at rest, they provide helpful fuel for active muscles. Instead of accumulating in the bloodstream where they can contribute to artery disease, these fuel molecules are used to produce energy.

In addition to canceling the negative effects of stress, exercise may induce some positive biochemical changes. Many exercisers report feelings of euphoria and states of consciousness similar to those described by people using drugs such as heroin. Such accounts have led to use of the term runner's high, since these descriptions first came primarily from long-distance runners (Mandell, 1979). These reports have intrigued both exercise scientists and the lay public and have suggested the possibility that certain types of exercise, particularly vigorous exercise of long duration, may cause biochemical changes that mimic drug-induced euphoria (Goldfarb, Hatfield, Armstrong, & Potts, 1990).

    As scientists have come to understand something of brain biochemistry, some interesting hypotheses have emerged. The most publicized of these has focused on a group of chemical messengers found in the central nervous system (brain and spinal cord) called opioids, since they are similar in structure and function to the drugs that come from the poppy flower: opium, morphine, and heroin (Carr et al., 1981; Morgan, 1985). Beta-endorphins belong to this group. They not only inhibit pain but also seem to have other roles in the brain as well, such as aiding in memory and learning and registering emotions. It is difficult for scientists to measure opioid concentrations in the central nervous system of humans, but animal research has suggested that endogenous (produced by the body) opioid concentrations increase with level of exercise: more exercise, more opioids.

    Why are opioids produced? Some will answer, "Because exercise is painful." These chemicals may help the body recover from prolonged exercise, as they seem to enhance mechanisms important during this period: raising pain threshold, slowing heart rate, decreasing blood pressure, and enhancing parasympathetic tone (which leads to the relaxation response) while inhibiting sympathetic activity (the fight-or-flight response) (Thoren, Floras, Hoffman, & Seals, 1990).

    Other biochemicals may be involved in the exercise high as well. Some research has suggested that changes in the concentration of certain hormones and neurotransmitters may play a role in causing the positive mood associated with exercise. In particular, norepinephrine and serotonin concentrations have been shown to change with exercise, at least in animals. Since abnormal levels of these chemicals have been associated with depression in humans, some researchers have speculated that the antidepressant effect of exercise may involve improving regulation of these substances in the brain (Dunn & Dishman, 1991; Harte & Eifert, 1995; Harte, Eifert, & Smith, 1995). Another possibility is that the endogenous opioids interact with neurotransmitters in some synergistic fashion to produce euphoria and mood improvement.

Post-Workout Muscle Tone: Relaxation

Muscle tension at rest is called muscle tone. Muscle tone increases during stress, since muscle bracing is part of the physical stress response. Elevated resting muscle tension causes a wide array of stress-related musculoskeletal problems, as well as general feelings of fatigue, and mental and emotional stress. Physical activity, on the other hand, leads to muscle relaxation. A feeling of physical relaxation characterizes a good workout's afterglow. After working hard, muscles relax. One study measuring the electrical activity of muscle found that activities such as walking, jogging, and bicycling decrease muscle tension by over 50 percent for up to 90 minutes after exercise (deVries, Wiswell, Bulbulian, & Moritani, 1981). Physical relaxation translates into mental relaxation as well. This afterglow of relaxation is an important part of the antistress value exercise has for many people.

Rhythmic exercises such as walking, running, rowing, and swimming increase alpha-wave activity in the brain (Stamford, 1995). The electrical activity of the brain can be monitored in the laboratory using an instrument called an electroencephalograph (EEG). Alpha waves are associated with a calm mental state, such as that produced by meditation or chanting. The rhythmic breathing that occurs during some forms of exercise also contributes to an increase in alpha-wave activity. Rhythmic activity performed to music may be stress relieving in other ways as well (Estivill, 1995).

Some research suggests that regular exercise of moderate intensity may provide a sort of dress rehearsal for stress. Several studies have found that people who exercise regularly have an attenuated physical response to laboratory stressors such as difficult mental arithmetic tests (Blumenthal et al., 1990; Steptoe, Kearsley, & Walters, 1993). In other words, when facing laboratory stressors, exercisers had less of a sympathetic response than did nonexercisers. Other studies have found that physically fit subjects recover more quickly than sedentary peers from stressors such as cold exposure or emotional frustration (Crews & Landers, 1987; Dienstbier, 1991; Hollander & Seraganian, 1984). While physical stress responses were similar in both sedentary and fit subjects, variables such as stress hormone levels and heart rate returned to resting levels significantly faster in the fit subjects.

    Why? Researchers theorize that exercise itself mimics the physical stress response. Recall the work of Hans Selye, who called the stress response "nonspecific" (see Chapter 2). In other words, he discovered that laboratory animals respond in a physically similar way to all kinds of stressors: noise, cold, heat, electric shock, and exercise. Researchers have since noted that hormonal responses to stressors vary somewhat depending upon whether a person perceives the stressor as a threat or a challenge (Dienstbier, 1991), but Selye's theory may still help explain the stress-resistance effects conferred by physical activity. Your response to a session of moderately vigorous exercise resembles your response to stress: elevated metabolic rate, cardiac output, energy substrate levels, muscle tension, stress hormones, and so forth. Regular exercisers return more quickly to resting metabolic rate than sedentary folks. Regular exercise also "teaches" the body how to recover from the emotional stress response as well. This idea is known as the theory of cross-reactivity. Your reactivity to stress becomes conditioned by repeated exposure to the stress imposed by exercise.

Exercise Health Benefits Counterbalance Negative Stress Effects

One of the reasons exercise increases your long-term stress resistance is that even though stressors still arise, your stress response is better managed and does less physical harm (Roth & Holmes, 1987). Regular exercise has all sorts of beneficial health effects that help counteract the long-term wear and tear of chronic stress. While stress raises resting blood pressure, exercise lowers it. Stress increases blood clotting speed; exercise slows it. Stress raises blood sugar; exercise brings it back down. Exercise therefore reduces vulnerability to the negative health effects of excess stress.

The physical part of physical activity may be only part of the stress resistance story. It is likely that the psychosocial aspects of participation in physical activity contribute to the stress resistance effects of exercise as well. Some psychologists have theorized that it is not exercise per se that makes people feel better, but the distraction from stressful stimuli that occurs during physical activity (Bahrke & Morgan, 1978; Raglin & Morgan, 1987). Picture this: a day that goes from bad to worse. The alarm doesn't go off so you sleep through your first class, you don't have time to prepare the assignment due for your next class, and you fail a pop quiz in your afternoon lab. Stress overload: you decide to go for a walk off campus, away from the college world. As you walk, your mind begins to wander and pretty soon you are thinking about your upcoming vacation. When you return to campus, life does not look so bad. Tomorrow is another day.

    While the distraction provided by physical activity probably makes an important contribution to stress resistance, the distraction value of exercise appears to be only part of the explanation for its stress-reducing effect. Studies comparing other forms of distraction to the distraction provided by exercise suggest that exercise seems to have a longer lasting anxiety- reducing effect (Raglin & Morgan, 1987). In other words, something about exercise over and above distraction helps decrease anxiety. Nevertheless, the distraction hypothesis helps explain why physical activities of very low intensity can reduce feelings of stress and improve mood. Activities such as archery, shooting, and bowling do not call forth the physiological changes associated with vigorous exercise, but they have still been associated with stress reduction. When you are actively engaged in tasks demanding concentration and motor skills, it's hard to keep your mind on your worries.

    Several other psychosocial factors may contribute to the stress resistance effects of exercise (Jasnoski & Holmes, 1981). Exercise may relieve boredom or provide opportunities for social interaction. By improving health and fitness, physical activity may help people feel better, and feel better about themselves (Benedict & Freeman, 1993). If exercise improves physical appearance-for example, with weight loss or better muscle definition-self-esteem and self-image may also improve (Brown & Harrison, 1986; DeBenedette, 1988; Howard, Cunningham, & Rechnitzer, 1984; Young, 1985). Physical activity is often enjoyable (Ornstein & Sobel, 1989), and as such confers wonderful health and stress management benefits.

EXERCISE BENEFITS

So far, exercise benefits have been discussed from a stress management perspective, but exercise has a number of other important benefits as well. If you decide to begin (or change) an exercise program to increase your stress resistance, you may wish to maximize health and fitness benefits while you're at it. The health and fitness benefits of exercise depend on what kind of exercise you're performing.

Aerobic exercise refers to activity that significantly increases metabolic rate for prolonged periods of time (15 minutes or longer). Brisk walking, rowing, cycling, cross-country skiing, and vigorous sports like basketball, squash, and soccer are all examples of aerobic exercise.

    Cardiovascular or aerobic fitness is a benefit of regular aerobic exercise and refers to improved fitness of the body's cardiovascular and energy production systems. You know your aerobic fitness has improved when you can perform a given amount of work (such as climbing a flight of stairs) with less effort.

    Aerobic exercise improves cardiovascular health and decreases risk of artery disease. It does this by strengthening the cardiovascular (heart and blood vessels) system and by helping to control several important artery disease risk factors. Aerobic exercise improves fat metabolism and blood lipid profile. You learned in Chapter 3 that LDL cholesterol is associated with an increased risk of artery disease. Another lipoprotein, high-density lipoprotein (HDL) reduces risk for artery disease, because HDLs appear to transport cholesterol out of the arteries and back to the liver. Exercise increases HDL-cholesterol levels. It also increases insulin sensitivity, the ability of your body to respond to the presence of insulin in the bloodstream, thus improving blood sugar levels and decreasing risk of type II diabetes. People who exercise regularly are less likely to develop high blood pressure, and regular physical activity may also help lower blood pressure in some people with high blood pressure. With aerobic exercise, blood platelets (responsible for making blood clots) become less likely to clump together, so the danger of obstructive blood clots that could cause a heart attack or stroke is lower for regular exercisers.

    All these exercise effects are short-lived; they are apparent for only hours to a few days following the last bout of exercise. What type of aerobic exercise you do is not so important as the fact that you keep doing it (McArdle, Katch, & Katch, 1996). Fortunately, these benefits accrue at all levels of exercise. While higher intensity exercise leads to greater improvements in fitness, even low-intensity exercise such as walking (Duncan, Gordon, & Scott, 1991) appears to be very beneficial in promoting the heart-healthy changes described above. Because it requires increased energy production, regular aerobic exercise is the best way to burn calories and is an essential component of any weight-control program.

Resistance Training

Resistance training occurs when you exert force against something that resists, such as elastic bands or a stack of weights. Resistance training increases muscular strength and muscular endurance. Muscular strength is a type of force and is measured by the amount of weight you can lift. Muscular endurance is measured by how many times you can perform a given movement.

    Your muscles, bones, and joints adapt to the demands of resistance training by becoming stronger. Denser bones are more resistant to osteoporosis, a disease in which bones gradually become weaker due to the loss of bone mineral. Weight-bearing aerobic exercise, such as walking and tennis, in which the bones must bear the body's weight (as opposed to swimming in which the water bears the body's weight) also helps increase bone density. Stronger muscles and joints are less prone to injury and help you stay active as you get older. Resistance training can also increase muscle size. Metabolic rate is relatively high in muscle tissue, so the more you have, the higher your metabolic rate will be, even at rest. The higher your metabolic rate, the more calories you burn, and the more you can eat without gaining weight. Some studies suggest that resistance exercise can also increase cardiovascular fitness, especially in people with relatively low fitness levels (McArdle et al., 1996).

Stretching

Flexibility refers to the range of motion in a joint. Adequate joint flexibility prevents injury and chronic musculoskeletal problems such as low-back pain. Like strength, flexibility declines as you age. Regular stretching can slow this decline and reduce the stiffness that limits physical activity (McArdle, 1996).

How MUCH Is ENOUGH?

The answer to the question of how much exercise you need depends on your goals. The bottom line answer is that something is better than nothing, and a moderately vigorous program that includes some variety in activities is better still. Numerous studies have concluded that a sedentary lifestyle is as dangerous as smoking in terms of risk for cardiovascular disease. Many public health organizations have rallied in response to these findings and have concurred on the following recommendation: get at least 30 minutes of moderately vigorous activity almost every day (Pate et al., 1995). This 30 minutes need not be performed at one time. Students may get this 30 minutes simply by climbing several flights of stairs a day and walking briskly around campus to their classes and activities. This bottom line amount provides some health benefits and at least keeps you out of the sedentary category.

    What if you don't have 30 minutes to exercise? Then try 20. If you are accustomed to doing no physical activity whatsoever, your goal is simply to introduce activity into your routine. A 15- minute walk may be a good beginning for someone who is currently sedentary. The two most important recommendations are these: start small, and anything is better than nothing!

    If you are new to exercise, build your exercise program gradually. Maybe 15 minutes of walking every day is enough for now. Remember that the worse your physical fitness is, the sooner you will see and feel results. Remind yourself that you are committing for the long haul because a lifetime of physical activity is what counts. Your objective for the first few months is to stay injury free and healthy, have a good time, and set up a routine that's going to become a lifelong habit.

BASIC HEALTH-FITNESS EXERCISE RECOMMENDATIONS

If you were to ask an exercise specialist for recommendations on an ideal exercise program for a healthy young person that would give the greatest amount of healthfitness benefits with the least investment of time, the recommendations would look something like this:

Aerobic exercise appears to be beneficial even at fairly low intensities-but the lower the intensity, the longer you should exercise. In other words, 20 minutes per session is long enough if you are working at a relatively vigorous level. If you are walking at a moderate pace, 45 minutes to an hour would be a better length.

In addition to these basic recommendations, don't forget that daily activity of every kind contributes to physical fitness, good health, and even to stress management. Take the stairs instead of the elevator, walk on your errands, work in the garden, play with children. All burn calories and contribute to a high-energy lifestyle that reduces risk of artery disease.

Some risk of injury is part of a high-energy lifestyle. Everyone is at some risk, no matter how old, how fit, how experienced, or how careful. Nevertheless, do everything you reasonably can to prevent injuries. Injury is one of the main reasons people quit exercising and can turn an avid fitness enthusiast into an exercise dropout.

    The most common injuries for adult recreational exercisers are overuse injuries, which usually result from improper training techniques and doing too much too soon. When you exercise, your body adapts to the stress imposed by activity by becoming stronger. The physical changes that occur are called the training effect: stronger muscles, a more efficient heart, and a better ability to metabolize fat. However, if there is too much stress, your body does not adapt, but weakens and breaks down. A few simple recommendations will help you understand how to exercise effectively and safely (Peterson & Renstrom, 1986).

Too often in an enthusiasm to follow recommendations regarding optimal amounts of exercise or to keep up with the athletic model in the video, beginning exercisers may do more than their muscles and joints are ready for. The result? Unnecessary aches, pains, and discouragement. Slow and steady wins exercise success.

Physical fitness improves when you ask your body to do more than it is accustomed to doing. You increase the distance, the pace, the intensity, the weight, the number of repetitions, or the duration of exercise. Exercise scientists refer to this increase as overload. It is important to increase overload slowly, generally by 10 percent or less per week. If you are walking a mile each session and you are ready to increase your distance, add a tenth of a mile to your walk. Slow, steady progress is the way to go, cutting back at the first sign of injury.

Begin your workout with a warm-up 10 or more minutes of gentle, repetitive movements involving all muscle groups, gradually increasing the intensity. Warm up for jogging by walking briskly and then jogging slowly, swinging your arms. Slow swimming warms you up for a swimming workout. You will know you are warmed up when you feel warm! A warm-up prepares your body for the demands of exercise. It increases circulation and energy production, and improves flexibility, strength, and coordination. Warm joints and muscles are less likely to get injured during your workout. A gradual warm-up is especially important for people unaccustomed to exercise and those with a history of heart disease. An adequate warm-up allows the heart to adjust to exercise and helps prevent an abnormal heart rate response (McArdle et al., 1996).

    At the end of your activity, cool down by gradually decreasing your exercise intensity. You may use the same activity as in your warm-up: a slower version of what you have been doing or simply walking. A cooldown helps your body adjust back to resting level. After exercise, the blood vessels supplying the skeletal muscles remain dilated, and if activity stops suddenly, blood may pool in the extremeties. This reduces the return of blood to the heart and brain, and may cause dizziness and even fainting (McArdle et al., 1996).

Make Time to Stretch

Stretching exercises are most effective when muscles and joints are warm. Stretching after physical activity (after your cooldown) will help you maintain or improve your flexibility. joints with adequate flexibility are less likely to reach the limit of their range of motion and suffer injury.

Some symptoms indicate possible need for immediate medical attention. These include irregular heartbeats; pain or pressure in the chest, arm, or throat; and dizziness, fainting, or confusion. More common are warning signs that you are simply overtraining and need to reduce training volume. These include soreness in muscles or joints, difficulty sleeping, loss of appetite and weight, and fatigue.

Pain is a message that something is wrong. Exercising before an injury has healed or when an overuse injury is in its early stages will only slow the healing process and possibly worsen the injury.

A good pair of shoes is one of the most important pieces of equipment for almost every activity. If your activities require safety equipment, be sure it meets industry standards and is as comfortable as possible. For example, people who play squash or racquetball should wear safety glasses. Cyclists should wear helmets and be sure bicycles are working correctly. In-line skaters should wear helmets and appropriate guards for wrists, elbows, and knees.

STAYING WITH IT

Starting an exercise program is the easy part. Sticking to an exercise program may take some effort. Here are a few suggestions to help you make physical activity a part of your life-for the rest of your life.

Choose activities that are fun and fit best into your lifestyle. If you can't take strenuous exercise, find an activity that requires a more modest effort. Use exercise to accomplish two goals at one time: get some exercise while you meet new friends, spend some time alone, or learn a new skill. And don't forget to have fun!

    When it comes to stress reduction, personal exercise preferences are extremely important. While exercise may increase stress resistance under the right conditions, exercise can also increase feelings of stress under the wrong conditions. For example, perfectionists may find the demands of following the perfect exercise program one more thing to worry about. Busy people may find an exercise program yet one more thing to fit into their overloaded days. If your exercise plan includes activities that are not enjoyable, even distasteful, the stress of your upcoming workout may hover over you like a black cloud. The competition imposed by sports such as tennis, volleyball, and basketball can raise blood pressure and stress level. Ready to quit before you start? Don't! The benefits of physical activity will still be yours, but you need the right attitude, and an exercise program that is right for you.

Anticipate Setbacks and Plan for Recovery

Everyone experiences setbacks from time to time. Family and school responsibilities get in the way, travel interrupts your routine, the weather won't cooperate, illness keeps you in bed. Think about the sorts of things that are likely to keep you from sticking to your program, and plan ahead. Prevent setbacks when possible, but realize that they will occur. View them as a part of life due to unavoidable situations and not to your personal failure to overcome all obstacles. Forgive yourself, make necessary adjustments, and get back into your program as soon as possible.

How easy it is to get bogged down with the demands of the day. When schedules get tight, exercise is often the first thing to go. After all, other things just have to get done today. Long- term goals get put on hold as people scramble to meet short-term demands. Most people would agree that lifelong good health is one of their longterm (and short-term) goals. Neglecting self- care is penny wise and pound foolish. What good is meeting today's deadlines if you develop heart disease at a young age?

Remember the 80/20 rule from Chapter 7, that 80 percent of the good comes, in this case, from doing 20 percent of the exercise recommendations. If there is no way to fit all the recommended activity into your current schedule, give yourself a break. Recognize that you have other things in your life besides your exercise program, and just do your best! Decide which 20 percent of the recommendations will help you the most and start with that. For example, an exercise class that meets twice a week and includes some aerobic exercise, some muscular strength and endurance exercises, and some stretching would only take two hours a week and would give you a great deal of fitness benefit.

We all love instant results. The media abound with advertisements for products that promise unrealistic weight loss, muscle toning, and body sculpting. So we expect great changes from an exercise program. An appropriate exercise program does have many health and fitness benefits, but they don't happen overnight. After six to eight weeks of regular participation you will begin to notice some progress: maybe better muscle definition, a little more energy throughout the day, an easier time climbing the stairs, a period of calm after your workout. As your program continues, you will see more changes. Fitness improvement happens fastest and is most obvious in those most out of shape to begin with. Some exercisers may find that after several months or even years of exercise they maintain a sort of personal inshape plateau. This may sound discouraging, but there is something to be said for maintaining fitness because fitness tends to decline as we age.

    What if this personal in-shape plateau does not lead you to perfection? You don't have to look like an Olympic bodybuilder to be healthy (in fact, bodybuilders often aren't!). Each of us is born with a genetic limit on body shape and muscle development. Most of us also have limited time to exercise and other priorities in life. To improve beyond our personal in-shape plateau may take the kind of time and effort that is simply not available.

TABLE 10.1 Health and Fitness Goals

Health and Fitness Goals       Activity Recommendations                        

___________________________________________________________

FIGURE 10.1 Physical Activity Readiness Ouestionnaire

Source: S. Thomas, 1. Reading, and R. J. Shephard. Revision of the  Physical Activity Readiness Questionnaire (PARQ). Canadian Journal of Sport Science. 17: 338-345, 1992.

SUMMARY

1. Participation in regular physical activity is one of the most effective ways to increase your stress resistance.

2. Physical activity has both short- and long-term effects. It relieves stress during and immediately following the exercise session. People who exercise regularly also report feeling less stressed even on days when no exercise occurs.

3. The term physical activity refers to all types of movement; exercise refers to activities intentionally performed to improve physical fitness.

4. Research has shown that almost every kind of physical activity can deliver stress management benefits, depending on personal activity preferences.

5. Exercise, especially vigorous exercise, may increase levels of beta-endorphin which is associated with relaxation and pain relief.

6. Exercise may change the concentration of other hormones and neurotransmitters, such as norepinephrine and serotonin.

7. After a workout, muscles are relaxed.

8. Rhythmic exercise has a calming effect, as evidenced by alpha-wave brain activity.

9. Some research suggests that regular exercisers have an attenuated response to emotional stressors, at least in the laboratory. People who exercise regularly may also recover from stress more quickly.

10. Health benefits of exercise counterbalance the negative effects of stress.

11. Physical activity may increase stress resistance by providing a temporary distraction from stressors.

12. Physical activity may relieve boredom, provide opportunities for social interaction, and improve self-esteem. Physical activity may reduce feelings of stress because it is often enjoyable.

13. Aerobic exercise refers to activity that significantly increases metabolic rate for prolonged periods of time (15 minutes or longer). Aerobic exercise improves the function of the cardiovascular and energy production systems.

14. Aerobic exercise reduces risk of artery disease. It strengthens the cardiovascular system, improves fat metabolism and blood lipid profile, increases insulin sensitivity, and prevents hypertension. Aerobic activity also slows blood clotting rate and contributes to weight control.

15. Resistance training occurs when you exert force against a resistance. Resistance training increases muscular strength and endurance. It also increases the strength of bones and joints, making them less prone to injury. Resistance training may also increase muscle size, and thus, metabolic rate.

16. Stretching increases flexibility, which refers to the range of motion in a joint. Adequate joint flexibility prevents injury and chronic musculoskeletal problems such as low-back pain.

17. A sedentary lifestyle is as dangerous as smoking in terms of risk for cardiovascular disease.

18. Public health officials recommend at least 30 minutes of moderately vigorous exercise almost every day. This 30 minutes need not be performed at one time.

19. People interested in getting more than the minimum level of physical activity may wish to participate in a variety of activities. The following program will increase aerobic endurance, muscular strength and endurance, and flexibility:

20. To prevent injury, it is important to start slowly and increase overload gradually; warm up and cool down; make time to stretch; recognize symptoms that may indicate a need for immediate medical attention or a need to reduce training volume; and use good footwear and safety equipment.

21. To increase the likelihood that you will exercise regularly, find activities that are fun and rewarding; anticipate setbacks and plan for recovery; and make your health a priority. Remember that doing even a little bit is better than doing nothing. Keep expectations positive but realistic.

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