Challenging Dogma - Spring 2008

...Using social sciences to improve the practice of public health

Thursday, May 7, 2009

Exercise is Medicine: A Poor Prescription for Physical Activity Promotion – Maureen Harris

Regular physical activity is a critical component of a healthy lifestyle and has a strong role in health maintenance and promotion. Exercise has been shown to reduce the risk of chronic diseases such as cardiovascular disease, diabetes, and cancer; promote quality of life; aid in maintenance of a healthy weight; reduce symptoms of depression; and enhance functional health (1-2).
Despite the manifold benefits of being physically active and risks of being inactive, adherence to the recommended guidelines for activity is remarkably low. The American College of Sports Medicine (ACSM) and the American Heart Association (AHA) recommend 30 minutes of moderate-intensity daily physical activity five days per week (3), and the 2008 Physical Activity Guidelines for Americans released by the Department of Health and Human Services (DHHS) calls for a minimum total accumulation of 150 minutes of moderate physical activity per week (4). Nearly two-thirds of adults in the United States do not meet these recommendations, and a quarter do not exercise at all (5). This has clear and severe public health implications.
The “Exercise is Medicine” Initiative
To address this burning issue, hundreds of small- and large-scale interventions have been developed, yet the problem persists. Many of these programs are based on faulty or tenuous theories or, worse yet, are not based on any framework at all. The Exercise is Medicine (EiM) initiative (6), sponsored by the American College of Sports Medicine (ACSM) and the American Medical Association (AMA) seeks to improve rates of physical activity through encouraging a dialogue about exercise between patients and health care providers. Despite the best intentions, this program, like the others, is fatally weakened by multiple flaws.
The program’s goal is to make physical activity a standard “vital sign.” EiM calls upon health care providers to assess patients’ activity levels at every office visit and to counsel patients on how to become more active. Providers are encouraged to “prescribe” exercise for disease treatment and prevention just as they would prescribe a pharmaceutical as well as to refer patients to fitness professionals just as they would refer to a medical specialist. Additionally, EiM instructs patients to ask their doctors about exercise. The program’s website provides reference materials for providers to facilitate dialogue with patients, and it offers “tool kits” and educational videos for patients to help them initiate an exercise routine. The initiative aims to link exercise with medical treatment and equate exercise with more traditional and familiar modes of treatment, such as pills. It promotes the long term physical health benefits of exercise while presenting limited information on other, more immediate benefits of exercise.
EiM appears to be based on the Health Belief Model (HBM; 7-8), which presents four factors central to an individual’s health behavior motivation: perceived susceptibility (assessment of the likelihood of acquiring disease/condition), perceived severity (assessment of the physical and emotional hardship that may be experienced if the disease/condition is acquired), perceived barriers (assessment of obstacles to perform health behavior, such as cost, access, embarrassment), and perceived benefits (belief that a given action will be efficacious in preventing a negative outcome or minimizing its severity). Each of these factors is considered during decision making and, if the pros of the behavior exceed the cons, the individual will form an intention to engage in the behavior. Intention is assumed to result in behavior. EiM, following the logic of the HBM, emphasizes the risks (i.e., severity) of not exercising, assuming that if people know that they should exercise then they will exercise. Despite its good intentions, EiM’s design is fraught with lack of foresight and faulty logic that severely hinders its potential to improve adherence with national physical activity guidelines. Three fundamental issues with EiM will be discussed: the definition of exercise as a medical treatment, the choice of doctor-patient interactions as the mode of message delivery, and the failure to anticipate barriers.
Definition of Exercise as a Medical Treatment
Defining exercise as medicine is potentially damaging and counterproductive. While the definition is intended to convey the importance of exercise and stress its role in health maintenance, it is more likely to reduce intrinsic motivation to engage in physical activities. Intrinsic motivation is considered to be a desire to participate in an activity for the inherent satisfaction of the activity whereas extrinsic motivation is desire to participate in an activity for a reward distinct from the activity (9). Cognitive evaluation theory (CET; 10-11) proposes that intrinsic motivation relies on social-contextual factors such as perceived choice, autonomy, and enjoyment. Supporting this concept, self-efficacy and perceived satisfaction were shown to predict maintenance of physical activity (13). Presenting exercise as a treatment and as a "doctor's order" implies a lack of choice on the part of the patient. Moreover, by suggesting that exercise is something the patient must do, rather than something the patient wants to do, it undermines inherent enjoyment of, and desire to participate in, the activity (12). Deci and Ryan propose a hierarchy of motivation, including amotivation (no motivation), extrinsic motivation, and intrinsic motivation (11, 14). Extrinsic motivation is broken into four categories which are differentiated by the ratio of external to internal locus of causality. The most external category, external regulation, is associated with compliance and external rewards, whereas the most internal, integrated regulation, is associated with overlap between personal values and the activity. An individual has greater enjoyment of, and greater likelihood of maintaining, an activity when the locus of causality is most internal (9). Thus, intrinsic motivation, or deeply internalized extrinsic motivation, is critical for maintaining a physically active lifestyle. Through its disregard for the components necessary for intrinsic motivation, EiM substantially weakens its ability to promote physical activity. Worse yet, it may even have the unintended effect of decreasing physical activity by reducing inherent enjoyment of active hobbies (e.g., dancing, playing soccer) by suggesting that the reason for engaging in the activity is because it is necessary or "the right thing to do," rather than simply an enjoyable activity.
An additional issue with defining exercise as medicine is that adherence to medically prescribed regimes is often low (15-21), especially for difficult, complicated, or long term treatments. Poor adherence to medical regimes is even present when the consequences of non-adherence are severe, such as in the case of medication for coronary heart disease (21). Committing to an exercise routine requires significant effort and dedication, putting exercise adherence at great risk for low adherence. Although adherence is a difficult construct to assess, a review of the literature (22) found estimates of adherence between 4% and 93%, with most rates falling between 29% and 59%. A second review (23) found estimates of poor compliance in 30-50% of all patients, regardless of diagnosis or setting. These discouraging rates of adherence, especially considering the time consuming and long term nature of exercise that increase likelihood of low adherence, suggests that EiM's strategy of defining exercise as a medical treatment is misplaced. Lack of trust in physicians (24) or perceived discrimination (25) can cause patients to disregard their provider’s exercise “prescription,” further damaging the chance that patients will adhere to providers’ EiM recommendations.
Choice of Doctor-Patient Interactions as the Mode of Message Delivery
EiM aims to relay messages about the importance of exercise through doctor-patient interactions, but this limited strategy is a poor choice. First, many people do not have access to, or choose not to seek, healthcare services. People do not access health services for a wide range of reasons, including lack of insurance (26), lack of time (27), lack of nearby health facilities (28), and lack of trust in healthcare professionals or medicine (24). Rates of healthcare utilization are also low among minority groups (5, 29) and non-English speakers (30). Low income families may not have access to healthcare even if they have insurance due to barriers such as distance from healthcare providers and high financial costs beyond what is covered by insurance (31). The low rates of healthcare access and utilization among the uninsured and the consequent low rates of doctor-patient interaction in this population represents a significant weakness of EiM, particularly because members of low SES groups (1, 5, 32-33) and low education (1) have higher rates of inactivity and, therefore, are at greater need for exercise interventions than member of high SES groups. Among the general population, a 2007 study (34) reported that 21 percent of Americans has an annual preventive physical exam. This indicates that a large percentage of the population will not see a doctor unless they perceive a health problem requiring treatment, suggesting that many sedentary, but otherwise healthy people will not receive EiM's message. A recent review of health insurance and access (26) reported that 67% of adults, including both insured and uninsured individuals, had no contact with a health professional in the past year, similarly indicating EiM’s lack of reach.
Assuming patients have access to and seek healthcare services regularly, a provider’s advice may not result in increased exercise behavior. As previously mentioned, distrust (24) and perceived discrimination (25) in healthcare settings can cause patients to disregard doctors’ recommendations. Additionally, even if patients have a good trust relationship with their doctor and accept the message that exercise is medicine, intentions to exercise may improve without a corresponding increase in rates of exercise. The doctor-issued recommendation puts the responsibility to be physically active in the hands of the patient without addressing larger scale and upstream factors. Moreover, EiM’s success lies on the Health Belief Model-based premise that increasing salience of health risks associated with inactivity will increase intention to exercise. However, this logic is flawed and, even if intentions to exercise improve, behavior will not necessarily follow. The Health Belief Model assumes rational behavior, but it is clear that people often act irrationally. Moreover, the relationship between intention and behavior cannot be assumed. Research has shown that many who intend to engage in a behavior fail to do so (35) and that habits may inhibit the influence of intention on behavior (36). In order to improve behavior, EiM must do more than improve intentions to exercise through doctor-issued guidance.
Failure to Anticipate Barriers
A major flaw of EiM is its failure to anticipate barriers to exercise and its subsequent failure to address these barriers. The physical, “built” environment plays a substantial role in one’s choice to be physically active or inactive. Subjective assessment of physical activity in adolescents (37) and adults (38) as well as objective (39) measurement of physical activity in adults using accelerometers has shown that proximity to physical activity-related facilities (e.g., schools, parks, dance studios, YMCAs, swimming pools, bicycle rentals) increase engagement in physical activity. Similarly, the more convenient it is to exercise and the less convenient it is to be sedentary, the more likely an individual is to choose active over sedentary activities (40). Thus, the lack of areas and facilities suitable for exercise make it inconvenient and less likely that individuals will exercise, even if they know they should. Physical activity-related facilities tend to be less common in low SES and minority areas (37, 41). This barrier for low SES areas is particularly concerning because, as mentioned previously, rates of physical activity are lower in these population (1, 5, 32-33). An environment characterized by barriers to exercise will likely counteract the effect of increases in exercise intention motivated by EiM.
An additional, but related, barrier is the easy availability and convenience of alternative sedentary behaviors. According to behavioral economics, individuals weigh alternative choices based on costs and benefits as well as the proximity and tangibility of the costs and benefits (42). Behaviors with high immediate benefits and low immediate costs are preferred, even if high costs will be experienced later (43). The immediate costs of exercise (e.g., inconvenience, hard work, time, physical discomfort) are high and salient whereas the benefits promoted by EiM are distal and uncertain. Though exercise may reduce the risk of chronic disease, it is not a guarantee. Subsequently, from a behavioral economics perspective, a sedentary lifestyle may be perceived as more rewarding and higher value than an active lifestyle. While EiM aims to inform patients of exercise’s future health benefits, it focuses little attention on exercise’s more immediate benefits and does little to anticipate and downplay immediate costs of exercising. Evidence has shown that, given the choice between sedentary activity and exercise, most will choose sedentary activities (44). If access to sedentary behavior is restricted such that exercise is more convenient, however, exercise behavior increases (40, 45) demonstrating the utility of behavioral economics in exercise promotion programs. EiM’s failure to incorporate the ideas of behavioral economics inhibits its efficacy. Its chance of success would be far greater if it anticipated the barrier of readily available and tempting sedentary activities and encouraged perceptions of exercise as being more accessible and rewarding than sedentary behavior.
While the Exercise is Medicine program is intended to increase exercise behavior, its design has fundamental flaws that reduce its efficacy and may even be counterproductive. It oversimplifies the problem and the solution, creates potentially damaging associations between exercise and medical treatment, makes faulty assumptions, is too limited in scope, puts too much responsibility on the shoulders of individuals, and ignores substantial barriers. A novel intervention that capitalizes on social and behavior sciences theory and research would have higher chance of success in increasing exercise behavior and helping Americans reach national physical activity guidelines.

Active Communities Today: A Social Science-based Physical Activity Intervention – Maureen Harris
The Exercise is Medicine (EiM) initiative aims to battle the alarming prevalence of sedentary lifestyle and encourage adults to meet the national recommended guidelines for physical activity. Despite its good intentions, the program’s ignorance of social and behavioral principles greatly inhibits its efficacy. A previous critique of this program highlighted several crippling flaws. Here, an alternative program is proposed.
The Active Communities Today (ACT) initiative is based heavily on social science research. As its names suggests, it has three primary objectives. First, to get people active and moving, without necessarily framing exercise in a health context. Second, to engage communities, foster social support, avoid blaming individuals, promote policy changes to encourage activity, and to campaign for improvements in the built environment that facilitate physical activity. Third, to emphasize that the time for change is now; exercise behavior, not exercise intentions, will lead to public health improvements. These objectives are targeted by three key strategies that specifically address EiM’s fundamental weaknesses.
Strategy 1: Foster Intrinsic Motivation and Adherence
The EiM program defines exercise as “medicine” and employs medical terminology (e.g., “prescription”) throughout its materials. This definition is not only ineffective, but potentially counterproductive. By limiting the factors known to support intrinsic and internalized motivation, EiM reduces the likelihood that people will voluntarily choose to be active. The importance of protecting intrinsic motivation is more than theoretical. Applied research has shown that promotion of the factors that enhance internalization of motivation is positively related to exercise behavior (13, 46-49). ACT, guided by cognitive evaluation theory (CET; 10-11) and motivation research (e.g., 9-11, 14), promotes perceived choice, autonomy, self-efficacy, and the inherent enjoyment of physical activity to foster intrinsic/internalized motivation.
The program empowers people to make their own decisions and avoids directives and orders, with its primary goal being to allow exercise to become a naturally reinforcing activity. Through program materials and outreach events, ACT proposes a wide variety of activities, including competitive (e.g., road races and sports leagues), cooperative (e.g., recreational sports leagues and walking groups), and individual (e.g., health club workouts and swimming sessions) options from which people can choose, allowing people with all personality types to select an activity that is most appealing to them. The program recommends experimenting with nontraditional exercises (e.g., boxing or dance classes) to maximize interest and maintain satisfaction. Importantly, though abundant choices are offered, guidelines are provided. To make a noticeable public health impact, people must achieve a certain volume and intensity of physical activity. ACT advises participation in at least one activity for at least 30 minutes most days of the week in order to see short term benefits, such as increased energy and improved mood. As Whitehead notes (12), freedom of choice can be maintained within guidelines.
To enhance exercise self-efficacy, ACT encourages simple activities (e.g., brisk walking) as well as offering community classes and online tools to provide tips and skills on more complicated activities. At outreach events, fitness experts offer free consultations to help people design appropriate workout routines. While educational, the primary emphasis will be to encourage confidence. This aspect of the program is critical as self-efficacy has been shown to predict exercise behavior (46, 48-49) and adherence (13, 47).
ACT markets exercise as fun, with the goal of helping adults reconnect with the enjoyment of playful activity of childhood and to incorporate daily activity into their lifestyle. Defining exercise as a positive and pleasurable activity portrays physical activity as a satisfying choice. Furthermore, the expectation that exercise will be enjoyable increases the likelihood that an individual will perceive exercise as enjoyable. Cognitive biases often cause us to see what we want to see or experience what we predict we will experience (50). Positive exercise expectancies have been associated with exercise behavior (51).
By facilitating the factors necessary for intrinsic/internalized motivation, ACT simultaneously addresses EiM’s likely problem with poor adherence. A smoking cessation intervention that supported autonomy and perceived competence increased long term adherence to tobacco abstinence (52). Similarly, it has been demonstrated that those who adopt exercise as a personal value are more likely to adhere to regular physical activity (9).
Strategy 2: Employ Widespread, Effective Communication
As noted, many people do not see their doctor for various reasons. Even among those that do see a healthcare provider, many lack trust in him or her, meaning that directives from a provider may be disregarded. In order to communicate the core program messages effectively, ACT employs a multifaceted communication strategy.
To maximize distribution, print, radio, and television ads are used to broadcast ACT’s key messages widely. Posters are placed in public buses and trains as well as high traffic centers such as libraries, schools, and outside of grocery stores and banks. Radio and television ads are aired several times a week. Local outreach events featuring ACT representatives bring key concepts directly to community members. A website offers confidential guidance, encouragement, and tools to get started. Visitors to the site will be encouraged to offer suggestions for site improvements to maximize its utility (53). A network of message boards hosted on the site will offer a forum for social support and exchange of questions and answers. Importantly, medical experts will moderate the boards to ensure the accuracy of answers provided by community members. The site will also feature a space for individuals to get involved in policy change by reporting concerns (e.g., crime levels render neighborhood unsafe for outdoor exercise) and requesting changes (e.g., construction of bike lanes on city streets). This space is intended to open a dialogue between community members and policy makers.
In addition to being well-distributed, it is equally important that ACT’s communications are interpreted positively. This involves appealing to values of the intended audience (54), as assessed by pilot focus groups and survey samples, rather than the values of ACT staff. As an example, the program promotes commuting by bike rather than car to be “green” and doing house/yard work on your own rather than hiring landscapers to be thrifty. ACT’s materials and events feature a wide range of regular people with whom the target population can relate, including members of various racial and cultural groups, young and old, male and female. Beyond facilitating social learning (55), this shows that exercise is truly for everyone and helps develop imagery of people having fun being active. The aim is for members of the target population to begin to imagine themselves in an active lifestyle and consider adoption of an active lifestyle as an achievable goal.
Strategy 3: Reduce Barriers and Market Immediate Benefits
ACT is firmly based on behavioral economic principles and recognizes that there are infinite sedentary activities competing with exercise to fill the limited number of hours in a day. To portray exercise as a valuable choice, the short term benefits must be emphasized while short term costs are minimized (42). The program’s goal is to sell the idea that exercise is a small investment with a large immediate reward.
ACT works to reduce immediate costs by making physical activity accessible and convenient. A major obstacle in the widespread adoption of active lifestyles is the lack of exercise-friendly environments. With unsafe streets, car-dependent communities, and neighborhoods lacking recreational centers, finding opportunities to be active can be difficult, even if an individual has an intention to be active. In order to make improvements in physical environments, ACT works closely with government officials, community developers, and business leaders. The program sponsors grassroots organizations to campaign for change at the town and city level while opening a parallel dialogue with state and federal leaders. As mentioned in the second section, ACT involves the community members in this dialogue. Short term projects include establishment of bike share programs in urban centers. The long term vision is for development of high-density, “walkable” communities with low crime rates, low pollution, and abundant physical activity-associated facilities (e.g., recreational centers, swimming pools, tennis courts). These attributes are associated with higher rates of physical activity (e.g., 56-58), and a recent case study reported that increased access to recreational resources raised physical activity levels (59).
In addition to reducing structural barriers, ACT reduces perceived immediate costs by showing that exercise can be just as easy and uncomplicated as sedentary behaviors. The program website and print materials offer suggestions on how to incorporate simple exercise and non-exercise physical activity (e.g., walking for transportation, vigorous housework) into a daily routine. Moreover, it suggests inexpensive activities that can be done without leaving the house (e.g., exercise videos, jumping rope, dancing), and reminds people that if they cannot tolerate high intensity exercise, they can still reap benefits from higher frequency, lower intensity workouts.
Keeping in line with behavioral economic principles, the immediate benefits of physical activity are advertised much more heavily than long term health benefits. Program materials highlight increased energy and vitality, improved mood, higher quality sleep, improved mental functioning, reduction in mild depression, increased self-esteem, and even higher sex satisfaction. Fun activities that are considered pleasurable rather than painful (playing tag with the kids, playing tennis with a friend or spouse) are highlighted. To help physical activity gain an extra edge over sedentary activities, behaviors such as television viewing and video game playing are marketed as having few benefits. Time spent TV viewing has been shown to be inversely related to leisure time physical activity in women (60), girls (61), and adolescent boys and girls (62), suggesting that reducing TV viewing may encourage activity.
ACT is a broad, multifaceted program. It works primarily above the individual level to create large scale changes in the culture, physical environment, and social environment. In parallel, it targets individual level behavior by reframing exercise with positive terms and promoting exercise’s inherently reinforcing properties.

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