Regular Exercise even jonas INTRODUCTION First Thoughts Regular exercise provides many health benefits to those who engage in the activity(1-3). In addition to its direct benefits, regular exercise is an essential part of healthy weight management and any effective program to lose weight The broad public health implications of exercise therefore include its pivotal importance in dealing with the obesity epidemic (see Chapter 8 for mor details The following definitions apply to the commonly used term exercise Physical activity is "any body movement produced by skeletal muscles that results in a substantive increase over the resting energy expenditure Leisure-time physical activity is"an activity undertaken in the individual's discretionary time that leads to any substantial increase in the total daily energy ex penditure Excrcise is a form of leisure-time physical activity that is usually performed on a repeated basis over an extended period of time(exercise training with a specific external objective such as the improvement of fitness, physical performance, or health""(1) It is important to note that regularity, exercising on a repeated basis over an extended period of time, is included in the standard definition for exercise. Sessions, workouts and going to the gym are terms that are used interchangeably with regular exercise throughout this chapter ounseling The most recent U.S. Preventive Services Task Force (USPSTF) recommendation on counseling for regular exercise, issued in 2002(4) concluded that "there is insufficient evidence to determine whether counseling patients in primary care settings to promote physical activity leads to sustained increases in physical activity in adult patients. "More 148
CHAPTeR 6. REGULAR EXERCISE 149 recent controlled studies suggested that counseling for regular exercise in clinical practice may be effective in helping patients to become regular exercisers(5-7). Whether there is high-quality evidence to support exercise counseling in the primary care setting, patients may request advice on how to become more physically active. The goal of this chapter is to guide clinicians on how to provide exercise counseling to their otherwise healthy patients: the sedentary person who wants to exercise; the sedentary person who needs to exercise for risk factor modification and the exerciser who is looking for advice because of injury, burnout or a need for consultation and reinforcement. This chapter presents a practical guide, based on 20 years of experience in the field and an extensive lay literature, on how to effectively offer physical activity counseling. The approach presented in subsequent text therefore reflects an experience-based consensus on fostering leisure-time, health-promoting, regular exercise, for its own sake This chapter does not specifically address the role of regular exercise in either the treatment or management of diseases or pathologic conditions(such as hypertension), or rehabilitation, although many of the basic principles for helping any patient to become a regular exerciser would hold true BASIC CONCEPTS IN EXERCISE Epidemiology of Exercise Epidemiologic data show that regular exercise promotes general health while its lack, known variously as physical inactivity or sedentary lifestyle, increases the risk of a variety of diseases and negative health conditions. At the beginning of the chapter on Physical Activity and Fitness in Healthy People 2010(2)it is stated that Research has demonstrated that virtually all individuals will benefit from regular physical activity... Moderate physical activity can reduce substantially the risk of developing or dying from heart disease, diabetes, colon cancer, and high blood pressure. Physical activity may also protect against lower back pain and some other] forms of cancer(for example breast cancer). On average, physically active people outlive those who are inactive. Regular physical activity also helps to maintain the functional independence of older adults and enhances the quality of life for people of all ages. The 2004"Best Practices Statement"of the American College of S Medicine(ACSM)(8)states Physical activity offers one of the greatest opportunities for people to extend years of active independent life and reduce functional limitations a substantial body of scientific evidence indicates that regular
150 SECTION II. WHAT TO DO WITH THE INFORMATION hysical activity can bring dramatic health benefits to people of all ages and abilities, with these benefits extending over the life span... and improve the quality of life The position taken in both of these reports was shaped by four important developments that have taken place over the past half century(9). First, the biomedical community identifed and clearly described those aspects of physical fitness that are related to health. Second, the scientific knowledge base underlying the original hypothesis that regular physical activity benefits health became firmly established. Third, the epidemiology of physical activity and inactivity has been studied and described in increasing detail over the years. Fourth, it has been recognized that both moderate and intense physical activity benefit health A major challenge is how to use all of our knowledge and understanding to actually help patients become regular exercisers at a level that is both comfortable and useful to them. Sound clinical advice, provided i an appropriate way by clinicians, can help patients unleash their own motivational process to become regular exercisers There are no known clinical trials of different approaches to the"nuts and bolts"of regular leisure-time exercise Controlled research comparing the effectiveness of one particular leisure-time exercise program versus another n fostering an ongoing pattern of regular exercise would be difficult to design and very expensive to conduct On the other hand, there is research on various exercise programs used as therapeutic interventions for the treatment of specific diseases and disorders. Therapeutic exercise regimens(and there are many very useful ones)are beyond the scope of this chapter Exercise: Aerobic and nongerobic There are two types of regular exercise based on level of intensity: "aerobic"" and"nonaerobic. "Exercise is considered aerobic when it is intense enough to lead to a significant increase in muscle oxygen uptake Nonaerobic exercise is any physical activity above the normal resting state involving one or more major muscle groups that is sustained but not so intense as to cause a significant increase in muscle oxygen uptake (Anaerobic exercise is intense physical activity, necessarily of very short duration [usually measured in seconds], fueled by energy sources within the contracting muscles, without the use of inhaled oxygen, most often incurred in competitive sports. It is not a factor in regular exercise. The heart rate is a simple measure to distinguish aerobic exercise from nonaerobic exercise. The exercise is considered to be aerobic when the pulse reaches or exceeds a level of 60% of the theoretical maximum normal, age adjusted heart rate(220- the persons age;0.6(220-age. It is important to note that this commonly used formula roughly approximates the true degree of increased oxygen uptake by the muscles (10) and is more accurate
CHAPTER 6. REGULAR EXERCISE 151 for measuring the intensity of exercise in beginners than in conditioned athletes. Most regular exercisers do not routinely measure their heart rate during their workouts, relying instead on subjective measures, such as deep breathing and sweating, to know when they are in the zone. Patients who are subject to extreme tachycardia should take their pulse while exercising To assure that exercise intensity remains at a safe level, the pulse rate should remain below 85% of the person's theoretical maximum age-adjusted heart rate(220- age) Although the evidence to date shows that exercise must be aerobic for it to be beneficial in reducing long-term risk for coronary artery disease exercise at any level above the sedentary state is helpful for weight loss and for producing the mental benefits associated with regular physical activity. An even modest level of regular exercise frequency(1 or 2 hours per week at nonaerobic intensity) probably reduces mortality. Moderate intensity physical activity other than regular leisure-time exercise, the so-called lifestyle approach, may also be beneficial for improving health and reducing mortality. Objectives for Reqular Exercise Given the known benefits of regular exercise and the harmful consequences of a sedentary lifestyle, the objectives for the activity can be set out in a straightforward manner. Regardless of the accumulated data about the long term health benefits of regular exercise, most regular exercisers engage in the activity because of the immediate benefits of feeling good and feeling better about themselves. When counseling patients about regular exercise, it is very important to bear this in mind. most regular exercisers do not engage in the activity in order to reduce their risk for future disease Risk reduction does not motivate most nonexercisers to start exercising either, unless a negative health event such as a heart attack shocks them into appropriate action,or they are exercising to promote weight loss. When patients ask about the benefits of regular exercise, the clinician should stress the short-term gains feeling good, improved personal appearance, and increased self-esteem. The clinician should point out though that most but not all sedentary people who become regular exercisers experience these gains. Long-term benefits will also motivate some patients and should be noted. Risks of reqular Exercise in the otherwise healthy Patient Regular exercise has its risks as well as its benefits. Virtually all of the risks are preventable or modifiable. The most common risk of exercise is injury. There are three types of injuries: intrinsic, extrinsic, and overuse. Intrinsic injury is that caused by the nature of the activity or sport, for example, shin splints in running. Extrinsic injury is that caused by an external factor, for example, a cyclist hit by an automobile. Overuse injury results from exercising too far
152 SECTION|· WHAT T○DOW| TH THE|NF○ RMATION too fast, too frequently. The latter is the most common cause of injury in most of the activities and sports used for regular exercise, such as running, fast walking, cycling, and swimming Intrinsic injury can be prevented by the use of proper equipment and correct technique. The risk of extrinsic injury can be significantly diminished by taking certain, mainly common sense, safety precautions, such as always wearing a helmet and never wearing a radio headset while riding a bicycle Overuse injury can be prevented by choosing a sport along with a workout schedule that are suitable to the exerciser, and by maintaining moderation in distance, intensity, and speed. The risk of a variety of pathologic problems is increased when a previously sedentary person engages suddenly in intense exercise or when a regular exerciser suddenly increases exercise intensity Therefore moderation and gradual change, if changes are to be made, are as always, good counsel GETTING UNDERWAY Recommendation"versus"Prescription Many clinicians use the term exercise prescription when discussing regular exercise with their patients. The term hails from the disease and medical models and appeals to many clinicians, especially those new to using the intervention. Prescription, however, usually means telling a patient to do something for a limited period of time. Regular exercise is by its very nature voluntary. No one can be forced to do it. Regular exercise requires more than just the temporary extra expenditure of time required to establish most other positive lifestyle changes such as engaging in healthy eating, achieving weight loss, and ' stopping cigarette smoking. For example, all people spend time food shopping, cooking, and eating. After learning about what changes to make, healthy eating requires only that the time be spent differently. After undergoing smoking cessation unseling and quitting tobacco use, no extra time need be spent again, Inless relapse occurs. In contrast, regular exercise requires a permanent commitment of time that would be otherwise spent doing something else. Of course, the maintenance of any successful behavior change requires constant attention for the rest of one's life, to a greater or lesser extent. However, in order to be most effective in counseling their patients to become regula exercisers, clinicians need to recognize the ongoing time commitment that regular exercise requires Therefore, because of its special nature, exercise cannot be prescribed like a drug. Rather, the clinician is recommending the effort to become a regular exerciser. The clinicians goal should be to develop a respectful and supportive partnership with their patients, using advice and counseling to assist them