Chapter 54 Social Influences and Physical Activity Rafer Lutz, PhD, Darwyn Linder, PhD, and Mike Greenwood, PhD   I can clearly remember trying out for my hometown little league baseball team when I was twelve years old. I had never played baseball competitively, but had been urged by my friends to play on the team. After barely making the team, I remember the experience as one of the best of my life – not because I loved baseball so much as that I liked playing ball with my close friends. I also remember climbing the rope in gym class. I was good at climbing because I was skinny, but I know some of the bigger kids in class hated it. One of my overweight friends made constant excuses about the rope being “too slippery” so that he could save some face when he only climbed a few feet up the rope. In fact, some of my friends hated gym class altogether simply because they didn’t like to dress down.  Presently, I notice how much my wife enjoys running with her group of friends in the mornings. Though now 8 months pregnant, she still goes to meet the group in the morning to walk with some of the group as they work on interval training. Each of these stories describes the power of social influences on our physical lives. Sometimes we are drawn to physical activity by friends and associates, but social influences may also drive us to avoid it. In this regard, this chapter is designed to survey the state of knowledge concerning social influences as they may sway our activity choices and behaviors. We are especially concerned with physical activity behaviors that have beneficial effects on the health and wellness of humans. Recent research (Paffenbarger, Hyde, Wing, Lee, & Kampert, 1994; Phillips, Kiernan, & King, 2001) has shown that virtually any physical activity has a beneficial effect when compared with being sedentary. Most research on social influence effects on physical activity, however, has focused on the traditional kinds of exercise prescribed for building strength, flexibility and endurance, namely, aerobic exercise and resistance training. We believe that many of the results we will describe in this chapter can be generalized to other kinds of physical activity in sports and games and in noncompetitive settings. It is also important to realize that there are costs as well as benefits associated with engaging in physical activity. The costs include discomfort, fatigue, energy expenditure, and time away from other activities. To overcome these costs and actually engage in physical activity may take more than just the expectation of the health benefits that will accrue in the future, and the intrinsic rewards of the activity itself. Social influence, in many different forms, may often be involved in the decision to exercise, play a sport, or even just to take a brisk walk. This chapter will explore some of the ways other people can influence our physical activity choices. Humans are by nature social beings. In trying to determine what makes us feel satisfied, psychologists have found that a feeling of social connection or relatedness is near the top of the list of what we need to experience (Sheldon, Elliot, Kim, & Kasser, 2001). We appear to be happiest when we successfully affiliate with others.  Stevens and Fiske (1995) theorize that our primitive ancestors’ survival was tied to group membership encouraging the development of our needs to belong, to be understood by others, and to maintain self-esteem. In modern society, social needs are still important and salient in daily life. Much of what we say and do is motivated by a desire to appear likeable, to gain social approval, to solidify group membership, to manage self-image, or to gain social support (Kenrick, Neuberg, & Cialdini, 1999). Physical activity behaviors may be affected by at least four types of social psychological influence: self-presentation, social influence (social norms and persuasion), social support, and group cohesion. Though distinctions between these categories are not always perfectly clear, they will serve to organize our thinking about social factors that shape physical activity behavior; therefore, this chapter examines research and theory in these broad categories. I. SELF-PRESENTATION A recent popular movie, “Catch Me if You Can,” describes the life of a man named Frank Abagnale who earned a reputation as one of America's most gifted con men. Abagnale, though only 16 years old, posed as a pilot for Pan Am Airlines, and later as a doctor, and a lawyer in his brief career of crime. After five years running around the globe, he was arrested and served time in French and Swedish prisons before his extradition to the United States where he was sentenced to 12 years in Federal prison. Eventually, he was granted an early release so that he could bring his expertise as a con man to fight crime with the FBI. During his time on the run, Mr. Abagnale told only one individual about his true identity. Not surprisingly, the woman in whom he confided quickly contacted the police (though he slipped away and was caught later). In an interview with the Australian Broadcasting Network in 1998 (Frank Abagnale - New Life, 1998), Mr. Abagnale recalls how he felt about being turned in, “And unfortunately, being 18 years old, 17, 18 whatever I was, I took that as a complete, OK, see, if you’re not a pilot or if you’re not parading as somebody, then people don’t like you. And if you don’t have a lot of money, then people don’t care about you. And the minute I told this person the truth, they turned on me.” The statement made by a young Frank Abagnale reflects why we may be so concerned about controlling the impression we make on other people. Because many of the things we want from life (e.g., jobs, praise, friendship, etc.) depend at least partly on others, we say and do things in attempts to make a favorable impression. The process of managing the image we project for others, or managing the impression we make on others is called self-presentation (Baumeister, 1982; Leary, 1995). Self-presentational concerns may have an impact on the friends we keep, the clothes we wear, our choice of career, the things we say, and even our attempts to lose/gain weight. Anytime we engage in a behavior or make a statement that is partly motivated to shape others’ views of us, we are engaging in self-presentation. Some people are more prone to self-present than others. Research has found that individuals high in self-consciousness or approval motivation are more likely to try to manage their impression on others (Doherty & Schlenker, 1991; Leary, Barnes, & Griebel, 1986). In a different vein, not all people engage in self-presentation to achieve the same goal. For example, it seems that individuals with high levels of self-esteem self-present in order to make a positive impression on others, while those with low levels of self-esteem self-present to avoid making a negative impression on others (Baumeister, 1982; Tice, 1991). We engage in self-presentation primarily to obtain resources we need and value, to create and construct a desired self-identity, and to help our social interactions proceed smoothly (Kenrick et al., 1999). How does self-presentation relate to physical activity behavior? There are several instances where self-presentational concerns may have a strong influence on our physical activity choices. Some people exercise to make themselves physically attractive to others. By changing their physical appearance through exercise, people may feel that it makes them more likeable and attractive to others. This is congruent with self-presentational theory considering that attractive people tend to be viewed as sociable, intelligent, or highly skilled (Feingold, 1992). On the other hand, failure to be physically active could also be motivated by self-presentational concerns. As Leary, Tchividjian, and Kraxberger (1994) note, “people who perceive themselves to be overweight, scrawny, or disproportioned may be reluctant to be seen bouncing around in aerobics class, swimming at the local pool, jogging in public, or lifting weights” (p. 466). Thus, self-presentational concerns may cause people to be either more or less physically active depending on how we perceive others’ views of our action and appearance. Body Image, Eating Disorders, and Obsessive Exercise It is a sad irony that obesity rates have soared in the United States over the past few decades (U.S. Department of Health & Human Services, 1996), while at the same time the “ideal” waist size for females may have become unhealthily smaller (Owen & Laurel Seller, 2000). The problem, however, is no laughing matter. Though body image concerns are reported as reasons for engaging in healthy physical exercise (Davis, Fox, Brewer, & Ratusny, 1995), some individuals are driven to engage obsessively in exercise perhaps trying to obtain an unrealistic body size (Gulker, Laskis, & Kuba, 2001), and others are driven away from physical activity because they are anxious about displaying their bodies in public settings (Treasure, Lox, & Lawton, 1998). In both of the latter cases, it would appear that individuals’ self-presentational concerns are leading to unhealthy choices. One of the diagnostic criteria for bulimia (DSM-IV: APA, 1994) is “recurrent inappropriate compensatory behavior in order to prevent weight gain, such as self-induced vomiting; misuse of laxatives, diuretics, enemas, or other medications; fasting; or excessive exercise” (p. 549). In extreme cases, therefore, self-presentational concerns may drive one to engage in too much exercise. Eating disorders such as anorexia nervosa and bulima are complicated disorders with many different causes, and certainly many of the causes of eating disorders are not directly related to self-presentational concerns. Yet, self-presentational concerns do appear to play a role in these disorders. For example, women with eating disorders tend to have a strong fear of rejection, and bulimics report that they are very concerned about making other people happy (Weinstein & Richman, 1984). Also, women with eating disorders suffer from reduced self-esteem and greater levels of social anxiety – two factors that may increase the likelihood of self-presentation (Leary et al., 1994). There is much yet to be learned regarding the extent to which obsessive exercise behaviors are adopted by eating disordered populations due to self-presentational concerns, and this may be an informative area of study. Though individuals with eating disorders may engage in obsessive exercise, not all obsessive exercisers appear to have eating disorders. Obligatory exercise can be defined as “a dominance of exercise in daily life and withdrawal symptoms if exercise is not possible. Addicts may exercise despite injury, at the expense of interpersonal relationships, to the detriment of their work, or with other negative consequences” (Rodgers, Hall, Blanchard, & Munroe, 2001, p. 152. Despite the use of the terms addiction and dependence in the literature, there is some controversy regarding whether exercise can truly become an addiction or whether people can become dependent on exercise (Hauck & Blumenthal, 1992; Pierce, 1994). It does appear, however, that some individuals are driven to exercise when they are injured, sick, or to an extent that is clearly beyond levels necessary for health benefit (Blumenthal, O'Toole, & Chang, 1984; Coen & Ogles, 1993). Though disputed, obligatory exercisers may be coerced by underlying physiological mechanisms associated with habituation to exercise (Allen & Coen, 1987; Mondin, Morgan, Piering, Stegner, & et al., 1996).  Yet, it also appears that self-presentational concerns may play a role in the motivation of obligatory exercise. Yates, Shisslak, Allender, Crago, and Leehey (1992) compared obligatory and non-obligatory runners, and found that obligatory runners (those who continue to run despite clear physical injury, sickness, etc.) were more concerned about weight and diet and were more preoccupied with their bodies. Gulker et al. (2001) found that obsessive exercisers showed greater obsessive-compulsive tendencies and scored higher on drive for thinness, body dissatisfaction and perfectionism. In contrast, Rodgers et al. (2001) did not find that appearance-related imagery was a significant predictor of obligatory exercise tendencies. There are a multitude of operational definitions of what constitutes overexercise, and it may be difficult to separate borderline eating disorders from obligatory exercise (Keski-Rahkonen, 2001). These issues have made it difficult to make accurate judgments about the importance of self-presentational concerns among obligatory or excessive exercisers. Again, future research may be directed to answer these questions more conclusively. Presently, research would suggest that obligatory exercisers have a greater preoccupation with thinness and body dissatisfaction. The source of the latter is yet open for debate as it may be a personal standard rather than a standard set for others’ benefit (and thus, self-presentation). Recently, Conroy, Motl, and Hall (2000) developed the Self-Presentation in Exercise Scale to allow testing of impression motivation and impression construction in exercise settings. Impression motivation reflects an individual’s desire to control others’ perceptions of them. Impression construction reflects how people change their behavior in order to influence others’ perceptions of them. The results of their initial validation work for this scale showed that impression motivation was positively related to the number of days per week individuals reported exercising. Impression construction was positively related to the percentage of social time spent exercising. This would suggest that exercise self-presentation concerns appear to cause individuals to exercise more frequently, though the direction of causality cannot be determined due to the correlational nature of the investigation. Though there has been scant research using this scale, it has promise to focus research that may determine how self-presentation influences exercise choices. Self-presentational concerns may also be expressed in the choice of the type of exercise or physical activity in which to engage. Sadalla, Linder, and Jenkins (1988) showed that there are distinctive stereotypes associated with participation in different sports and games. Undergraduates were asked to rate the personality characteristics of a young male who was described as being an active participant in one of five sports; bowling, tennis, golf, snow skiing or motocross. Five trait clusters emerged in the analysis that were labeled “active-daring,” “cultured,” “calmness,” “honesty,” and “sensual-attractive.” The motocross rider and the skier were rated highest on the active-daring dimension. The tennis player and the golfer were rated highest on the cultured dimension. The golfer was rated highest on the calmness dimension. The motocross rider was rated lowest on the honesty dimension. The skier and the tennis player were rated highest on the sensual-attractive dimension, while the bowler was rated lowest. The statistical analysis showed that these stereotypes were quite consistent across the 250 raters. What this indicates is that we have stereotypes about sports participants that differ depending on the specific sport chosen. Those stereotypes can then guide people in making choices about what kind of physical activity to select in order to build a desired social identity.  Lewis and Linder (1994) replicated and extended this research, adding running and aerobics to the list of sports, manipulating the degree of involvement as low, moderate or high, and manipulating the gender of the sport participant. Again, clear stereotypes emerged, but only if the level of participation was moderate or high. The cross gender ratings were particularly interesting, as stereotypes of males held by females, and of females held by males would be useful in impression management for purposes of attracting the opposite sex. Females gave the most positive ratings to male skiers, followed by tennis players and runners. Males gave the most positive ratings to female skiers and aerobics participants, also followed by tennis and running. Bowling created the least positive stereotype for both male and female raters of both male and female bowlers. Impression management and self-presentation are salient concerns for most humans, especially when meeting new people or entering new situations. The existence of stereotypes about participants in specific activities gives the impression manager some leverage in determining how he or she will be perceived by others. Thus, the choice of a physical activity may be influenced by these social concerns, as well as by specific characteristics of the activity itself. Social Physique Anxiety Social physique anxiety (SPA) is defined as the degree to which people are anxious or nervous when others are observing or evaluating their physique (Hart, Leary, & Rejeski, 1989). SPA has been found to relate negatively to body cathexis, body esteem, and interaction anxiety, but not social desirability (Hart et al., 1989). Thus, SPA appears to concern anxiety about our ability to present ourselves desirably in the physical domain, but not an overall desire to please others. SPA has been documented to be positively related to percentage of body fat and body dissatisfaction (Hart et al., 1989; Hausenblas & Fallon, 2002). Studies of reasons for engaging in exercise show that high SPA females report exercising to improve body tone, control weight, and improve physical attractiveness (Crawford & Eklund, 1994; Eklund & Crawford, 1994), confirming the impact of self-presentational concerns as a contributor to this type of anxiety. As Arkin (1981) notes, when people are engaged in self-presentation they may be motivated to acquire others’ approval or to avoid others disapproval. Considering the fact that people could make one of two choices when faced with anxiety about their bodily appearance – exercise more to improve appearance (to acquire approval) or exercise less to reduce the frequency of exposure of their body (to reduce disapproval), it is not surprising that the literature shows diverse findings. As an example of a study where subjects may have engaged in an avoidance self-presentation strategy, Treasure et al. (1998) examined a group of sedentary, obese female university students, faculty and staff. Older subjects exhibited reduced levels of SPA, and SPA showed a stronger relationship to program dropout for younger participants. The authors speculate that, because the exercise program took place in a setting where other young, male participants were present, younger female participants who had high levels of SPA were more prone to drop out. Older females may not have felt the need to engage in avoidance self-presentation because they were not concerned about undergraduate, male students’ impressions of them. Of course, it should also be considered that older age may reduce the likelihood that SPA will cause exercisers to engage in self-presentational strategies such as exercise avoidance. The popularity of the Curves fitness centers that exclude male exercisers also suggests that removal of potentially significant evaluators can boost exercise participation. Spink (1992) found that participants who exhibited high levels of SPA tended to exercise more in private settings where they would experience less evaluation. Lantz, Hardy, and Ainsworth (1997) found that SPA correlated negatively with scores on the Minnesota Heart Health Program Leisure-Time Physical Activity Questionnaire, and that this relationship was stronger for depressed males. These studies would indicate that SPA may cause many individuals to avoid exercise, or at least avoid public exercise settings. Some studies, however, have not shown a relationship between SPA and adherence or participation rates (Diehl, Johnson, Rogers, & Petrie, 1998; Krane, Stiles-Shipley, Waldron, & Michalenok, 2001), or that any such relationship may be accounted for by physical self-perceptions (Kowalski, Crocker, & Kowalski, 2001). Again, this is not necessarily contrary to theory because participants may be attempting to improve their appearance through exercise to allow better future self-presentation or attempting to avoid presentation. Thus, the evaluative aspect is left uncontrolled in these studies, so it is difficult to predict either a positive or negative relationship between SPA and exercise participation rates.  In a slightly different vein, research suggests that appearance motives provide strong incentive to participate in exercise. Research on obligatory runners has found that they are highly concerned about weight control and are highly preoccupied with their body (Yates et al., 1992). Imm and Pruitt (1991) found that high frequency exercisers were more dissatisfied with their body shape than moderate frequency exercisers or non-exercisers. Cash, Novy, and Grant (1994) found that many college females report exercising for appearance or weight management, but these women were more dissatisfied with their body than those who exercised for other reasons such as fitness or social contact. It appears that individuals who exercise to improve their appearance experience more negative affective states with participation than those who exercise for other reasons (Frederick, Morrison, & Manning, 1996). Despite what the latter findings suggest would occur, few studies seem to document a positive relationship between SPA and exercise participation. It appears that those who are highly anxious about their physique exercise less or only as much as other non-anxious individuals. In this regard, SPA may cause avoidance of others disapproval in more cases than it causes individuals to exercise to acquire gains in approval from others through a changed physique. Social Facilitation and Social Loafing Self-presentation concerns may not only influence whether or not we exercise, but our intensity of engagement as well. Worringham and Messick (1983) studied the effect of evaluation on running performance nearly 2 decades ago. They found that joggers (who were unaware they were being timed) ran faster when a lone individual sat watching them, than when the lone individual was reading and facing the other direction or when there were no other people in the area. The explanation for this effect has been termed social facilitation, which has been used to explain why performance may increase or decrease in the presence of others. The traditional explanation is that the presence of others causes an increase in physiological arousal, often due to evaluation apprehension. Applying drive theory to this phenomenon, it is predicted that this increase in arousal causes a greater likelihood that the performer will elicit his or her dominant response (Strauss, 2002; Zajonc, 1965). This means that performance on well-learned tasks will improve in the presence of others, while performance on complex or poorly-learned tasks will suffer in the presence of others. Reexamining the findings of Worringham and Messick (1983) in light of self-presentation theory, however, we might predict that joggers who were being watched by others had a desire to project a positive image to the observing confederate, thus causing them to run more quickly. While there is little research on this specific topic, anecdotal evidence would suggest that many people exercise more strenuously when others are watching. Of course, due to self-presentation theory, participants may also choose to abstain from exercise if they feel that poor performance in front of others will lead to a loss of social capital. In this manner, self-presentation concerns may also cause improved or reduced levels of performance, not unlike drive theory. Ultimately, both explanations may partly explain why people may push themselves harder or withdraw effort when others are watching. Social facilitation occurs when people feel that their performances are being evaluated, causing them to work harder. Yet, if people feel that their performances are not easily identifiable, they may engage in social loafing. This phenomenon is demonstrated by a study performed by Williams, Nida, Baca, and Latane (1989) who found that swimmers’ relay race times were faster when their performances were highly identifiable. In order to make performance more obvious to those around the pool, times were called out loud for participants during some races. Swimmers’ relay times were faster when times were called out in comparison to races where this was not done. The implication of this finding and other research that supports social loafing (see Hardy, 1990) is that it appears that people will reduce their levels of effort when their performances are not easily evaluated by others. In essence, people will not be as concerned about self-presentation when they are able to “hide” in a large group. This has several implications. For those who desire to get the most out of their clients in exercise settings, methods should be found to emphasize individual effort (e.g., call out performer’s names, wall charts, etc.). Yet, for exercise professionals who work with clients who may have social physique anxiety, exercising in large, anonymous groups may reduce self-presentational concerns and create a more comfortable situation for exercisers, though individual effort may also be reduced. Conclusions People make many different attempts to manage how others’ view them. Because other people control many of the things we want to obtain, such as friendship, financial resources, or career advancement, we strive to gain others’ approval or avoid rejection. In exercise and physical activity settings, these attempts to present ourselves favorably may have either positive or negative effects on our strivings to be physically active. Exercise professionals should be aware of the powerful influence of self-presentational motives. On the basis of this brief review of self-presentational issues several recommendations can be made.  One recommendation is that people should be encouraged to find physical activities that make them feel good about themselves. Because physical activities are associated with different stereotypes, people will likely be more successful if they choose activities with stereotypes with which they are comfortable.  Another recommendation is that physical activity environments should be structured so that evaluative concerns are reduced. Though exercise has the promise to change our physical appearance, and though many people exercise to achieve these benefits, these changes are usually very slow to occur. Further, it is likely that many people avoid physical activity because of body presentation concerns. Breaking classes into groups where evaluative concerns will be reduced (i.e., women only or over 50 men) may be a good idea.  A third recommendation is that individual rewards/punishment be used as motivators only for more established exercisers. It may be a good idea to allow beginners to hide in anonymity until they feel more comfortable in exercise settings. Though this may lead to some social loafing, at least they will not drop out of the class because they feel singled out and want to avoid feelings of rejection.  As a final recommendation, realistic body image ideals should be promoted. Many fitness companies use very highly fit spokespersons to advertise their latest diets, training devices, or training programs. Rather than focusing on appearance, exercisers should be encouraged to find something about their participation that makes them feel proud. In this manner, attention may be drawn away from body size to other features of an individual that the person might feel more comfortable projecting to others. A great example is the Leukemia & Lymphoma Society's Team In Training program, which is the world's largest endurance sports training program. Participants are not training to lose weight or tone their abs (though these may be secondary motivators), rather they are running a race or triathalon to raise money for Cancer research. This allows them to self-present a very favorable image (philanthropist), and take attention away from the self-presentation of their bodies. II. SOCIAL INFLUENCE If you have ever been in an audience at a large musical or theatrical performance, you may have noticed that the audience tends to clap in unison and stop clapping at the same time. You may have even started to clap when no one else did only to feel foolish and quickly stop clapping. What you are experiencing in these situations is the power of social influence – specifically, social norms and conformity. Social influence can be defined as a real or imaginary pressure exerted by others that shapes our behavior (Kenrick et al., 1999). Among some of the most interesting findings in psychology, people are often prone to conform to others’ expectations or yield to others’ requests or demands. While self-presentation describes our actions or attempts to project a positive image to others, social influence describes the pressure exerted by others to influence our action. In exercise and physical activity settings, there are numerous examples of the power of social influence. Joining a fitness club because other friends pressure you join, or your teenager’s desire to buy the latest pair of basketball shoes because Allen Iverson wears them and touts them on commercial television are both examples of the power of social influence. Social Norms and The Theory of Planned Behavior Social norms refer to accepted societal rules for behavior. Failure to follow such rules can result in unwanted consequences, while following these rules leads to acceptance in the societal group. Typically, social norms in exercise settings have been studied within the framework of the Theory of Planned Behavior (see Chapter on lifestyle behavior change). To explain motivation in health behavior change, this theory has examined subjective norms as one of three primary factors (attitude and perceived behavioral control being the other factors) that influence our intent to engage in exercise participation. In this context, subjective norm refers to perceived social pressure to perform or not perform physical activity behaviors.  According to the theory, these norms should influence our intentions to participate in physical activity, which in turn should influence our participation. This theory, however, has performed only moderately effectively for explaining health behavior change in exercise settings. Hausenblas, Carron, and Mack’s (1997) meta-analysis of the research conducted to examine this theory within physical activity contexts found that subjective norm showed a smaller magnitude relationship with both intent to exercise and exercise behavior than did other components of the theory (attitude and perceived behavioral control). This would suggest that though subjective norms appear to play a role in our decision to participate in physical activity, they do not play a large role. This finding has been confirmed in other reviews and more recent studies (Courneya, Plotnikoff, Hotz, & Birkett, 2000; Godin & Kok, 1996; Sheeran & Orbell, 2000). Yet, we must not be too quick to discard the idea that social norms have meaningful influence upon our physical activity behaviors. There are two possibilities for the failure to find a strong, consistent relationship between subjective norm and intent to exercise: 1) It is possible that another variable moderates the relationship between subjective norm and intent to exercise, or 2) it is possible that the relationship between subjective norm and intent varies depending on the type of norm being investigated (Okun, Karoly, & Lutz, 2002). Chatzisarantis and Biddle (1998) examined type of motivation as a moderator of the subjective norm – intent relationship and found that for those extrinsically motivated to engage in exercise there was a positive relationship between subjective norm and intent, while for those intrinsically motivated there was a negative relationship. One type of extrinsic reward is social recognition or approval, and it makes sense that people who exercise to gain such rewards are more sensitive to the influence of exercise norms. It is intriguing, however, that for those who are intrinsically motivated to engage in exercise, feeling a sense of social pressure to exercise reduces intent to exercise. This finding may be explained using Brehm’s (1966) theory of psychological reactance, which predicts that increased pressure to behave in a certain way, even if that behavior is intrinsically motivated, will increase the attractiveness of not performing the behavior. Okun and colleagues (2002) sought to determine if the type of norm investigated impacts the relationship between subjective norm and intent. Social norms can be divided into injunctive (what people feel others think they ought to do) and descriptive (what other people actually do) norms. Reno, Cialdini, and Kallgren (1993) found that injunctive (ought) norms were more useful for reducing negative, anti-social behaviors, while descriptive (actual) norms were more useful for increasing prosocial, positive behaviors. In Okun and colleagues’ study, injunctive norms did not predict either intent or exercise participation, but descriptive (actual) norms predicted both intent and exercise participation. Though descriptive norm did not have a very meaningful effect on intent, it did show a moderate direct effect upon exercise participation. The authors concluded that descriptive norms appear to have an effect on the action of exercise participation, but not the motivational or decisional process for exercise participation. Further, they conclude that it is premature to state that social norms do not have important influence on physical activity behaviors, and that attempts should be made to examine how descriptive norms exert their apparent direct influence on exercise participation. Another consideration is that social norms may influence physical activity with more or less potency depending upon one’s gender or age group. De Bourdeaudhuij and Sallis (2002) surveyed over 2,300 Belgian young, middle-age, and older adults about their physical activity participation. It was found that different types of influences related to physical activity for different age and gender subgroups. Demonstrating the importance of social influences, in five of the six subgroups studied (older females being the exception), social variables were the most effective for explaining variance in exercise participation. Interestingly, the perception that friends or family wanted subjects to exercise, which was defined as a social norm, was significantly and positively related to exercise participation only for older males. Yet, it is unclear why injunctive social norms should relate to exercise participation in older males more so than in other populations. Researchers have speculated about the different potential sources of social influence and their impact (e.g., friends, family, etc.) (Chogahara, 1999). It may be that older males are specifically targeted as objects of social influence, that social norms gain greater influence as perceived health threats become more salient, or because they are responding to social norms conveyed from a different source than are other groups (i.e., physician’s advice). The latter is mere speculation, however, and it remains to be determined how or why different age or gender groups are influenced by social norms. An appraisal of the existing literature concerning social norms leads to several conclusions. It appears that injunctive/ought norms have only a weak influence on our participation choices. However, as documented in older males and among those engaged in physical activity primarily to obtain reward or recognition, this type of social influence may be meaningful in some populations. Further, we cannot dismiss the importance of social norms in physical activity based on Hausenblas et al.’s (1997) review because descriptive/actual norms provide a moderate, direct effect on participation. Though the reasons for these different effects are not particularly clear, it is evident that social norms have a sizeable influence on individual physical activity choices. Simply, the magnitude of this influence appears to be determined by the type of norm, and an individual’s motivational type and population subgroup. Attitudes and Persuasion The Theory of Planned Behavior (TPB) postulates that, in addition to social norms, attitude is another factor that influences our intent to exercise and ultimately our physical activity behavior. Attitudes are favorable or unfavorable reactions to particular people, ideas, events, or even behaviors such as exercise, and according to this theory, attitudes are composed of beliefs about the outcomes of the behavior and evaluations of such outcomes (Ajzen & Madden, 1986). For example, one might believe that physical activity will reduce the likelihood of premature death and evaluate this as a desirable outcome. On the other hand, one might believe that physical activity does not significantly impact long-term health and that it is not fun and that these are not desirable outcomes. In studies examining the TPB, intent to exercise and actual exercise participation are both predicted consistently by attitudes about exercise and physical activity (Godin & Kok, 1996; Hausenblas et al., 1997; Okun et al., 2002). How then can we persuade people to view exercise as leading to desirable outcomes? Persuasion is “a change in a private attitude or belief resulting from the receipt of a message” (Kenrick et al., 1999). While we may be bombarded with messages about the long-term benefits of physical activity, they may still fail to persuade us that exercise actually leads to these outcomes or that these outcomes are desirable. Only when one changes his or her internal attitude, has he or she experienced persuasion. This distinction is significant because information concerning the benefits of exercise and physical activity is very common, yet people may not be persuaded to exercise based on these messages. Some attitudes are more resistant than others to change. Pomerantz, Chaiken, and Tordesillas (1995) argue that attitudes are resistant to change when people are certain that they are correct and committed to an attitude and when people have an attitude that is embedded with respect to who they are. Also, people are not likely to be persuaded if they do not think too much about the persuasive message. The elaboration likelihood model developed by Petty and Cacioppo (1986) predicts that lasting attitude change will not occur if the recipient of a message does not engage in deep thinking about the content of the message. Several factors are proposed to cause individuals to think deeply about a message – its personal relevance, one’s personal tendency to engage in deep thinking, and the ability or time to process the message in a thorough fashion (Kenrick et al., 1999). It is probably not likely that an individual in his or her 20s or 30s will think deeply about a message warning them that inactivity may lead to cardiovascular disease and premature death. This message would have more personal relevance, however, if an individual had a family member who died of a heart attack or if they had suffered one themselves. The latter individual should feel that the message has personal relevance and be more likely to think deeply about its content. Many attempts to persuade people to adopt health facilitating behaviors warn of the dire consequences of failing to take the recommended action. Research has shown that appeals based on arousing fear of the negative consequences of failing to follow the communicator’s recommendations are most likely to fail to persuade the target persons, unless the fear arousal is followed by explicit instructions to take specific actions that are within the capability of the target audience. Leventhal, Watts, and Pagano (1967) targeted a reduction in cigarette smoking as the recommended outcome. They showed some participants a very frightening film about the consequences of smoking, including extremely graphic scenes of a lung cancer operation. Some participants were then given a pamphlet that included explicit instructions on what steps to take to stop smoking. Other participants only saw the film. A third group did not see the film but did receive the pamphlet. The researchers then called the participants one week, two weeks, one month and three months after the experimental session and obtained a self report measure of the number of cigarettes smoked daily. The results were quite striking, the group that had viewed the film and received the pamphlet, who had been frightened but also given directions on how to quit or reduce smoking, showed a significant and long term reduction in smoking. Those who had not seen the film, but had received the pamphlet, actually increased the number of cigarettes smoked for a short time and then returned to baseline. Those who had seen the film, but were not given the pamphlet, showed an initial decline in smoking but then returned to near baseline consumption. While this experiment focused on smoking reduction or cessation, it is quite applicable to situations where the dire consequences of physical inactivity are forcefully presented to an audience with the intent of persuading them to exercise. The audience is much more likely to be persuaded if specific recommendations for actions they are capable of taking follow closely after the fear arousal. People are also more likely to be persuaded by some individuals more than by others. For example, my grandmother’s attempts to persuade me that lima beans are good for my health will not be as influential as the same message coming from the U.S. Surgeon General. Simply, an individual will be more persuasive if he is seen as trustworthy and having pertinent expertise (Perloff, 1993). An interesting method that can be used to increase trustworthiness is to state minor arguments against your claim before introducing your persuasive statement (Eagly, Wood, & Chaiken, 1978). For example, it might make me more credible to argue that exercise is time-consuming before making the statement that it can make you feel better in the remaining time that you have. Yet, people do not have to be experts or even necessarily trustworthy to be effective at persuading others, sometimes they only need to be well-liked. According to Heider’s (1958) balance theory, people want to view the world in a consistent manner. In other words, if your favorite actor is Arnold Schwarzenegger but you do not like bodybuilding because you think it is narcissistic, you are likely to change either your opinion of Arnold or bodybuilding in order to achieve harmony. In this manner, it is wise to choose spokepersons who are well-liked, respected as experts, and trustworthy in order to “sell” a given message.     Effectiveness of Interventions to Promote Physical Activity Mass Media Approaches Recall of messages tends to be quite high. Significant improvements in knowledge of the benefits of physical activity have rarely been found. Repetition of the message does not appear to improve knowledge of physical activity benefits or intent to exercise. Ability to influence actual physical activity participation is "debatable." Smaller Scale Print Media and/or Telephone Approaches Appear to improve motivational readiness to engage in physical activity. Effectiveness may be improved if print materials are based on recipients stage of change/readiness to engage in physical activity. Majority of studies report increases in physical activity behavior. Telephone contracts appear to promote adherence, particularly if performed frequently. Media-based approaches that allow for flexibility appear to outperform "structured" messages. It is currently difficult to determine which types of approaches (face-to-face counseling, print media, telephone contact) may be more or less effective if used in isolation because most studies used a combination of approaches. Approaches Targeting Underserved Populations Results of five studies found show mixed results.   Figure 1. Conclusions of Marcus et al. (1998) regarding the effectiveness of different types of media interventions to persuade people to increase physical activity. In physical activity contexts, researchers have examined the persuasive process primarily by investigating how mass media messages, direct mailing campaigns, video training, seminars, and a variety of other interventions have been able to influence people’s attitudes about physical activity, knowledge of the benefits of physical activity, and adoption of physical activity behaviors. Marcus, Owen, Forsyth, Cavill, and Fridinger (1998) provide an excellent review of this literature, and Figure 1 summarizes their conclusions based on the different types of interventions employed to achieve behavior and/or attitude change. Many of the studies included in Marcus and colleagues’ (1998) review used a social marketing framework in their implementation and design. Social marketing is more than just persuasion, though there is a strong persuasive element. It involves consideration of design, method of delivery, and management of programs that attempt to make a social idea or practice more desirable or well accepted (Kotler & Roberto, 1989). While the studies reviewed by Marcus and colleagues did not always show a change in exercise participation, it is also important to consider other changes an individual may experience upon receiving the message. In the social marketing approach, behavior change is only one component in a larger hierarchical system of communication (Donovan & Robinson, 1992), and constructs that are likely impacted before behavior change may include knowledge, attitudes, or intentions. As Donovan and Robinson argue, many mass media campaigns may have been deemed more successful if outcomes other than behavior change were examined. Inactivity may be a difficult habit to break, and persuasive interventions designed to achieve attitude change may only provide a base for altering activity patterns. Future research is required to better determine how such outcomes may be influenced by mass media, print media, or other persuasive approaches. One area that may be particularly important to study concerns how to best persuade particular cultures that physical activity is a valuable activity that produces desirable outcomes. Because attitudes are theorized to lead to intent and ultimately action, it is of interest to determine how attitudes about physical activity differ across different populations. One reason for differential physical activity rates across cultural and/or ethnic groups (Jones et al., 1998; U.S. Department of Health and Human Services, 1996) may be different attitudes or beliefs held by these groups. The extent to which cultural attitudes influence physical activity participation is not presently clear. Research indicates that African American and Native American women both believe that physical activity is good for them (Henderson & Ainsworth, 2001), yet it is less apparent whether different ethnic or cultural groups see health benefits as desirable. Likewise, older Mexican Americans and European Americans report similar perceptions of the benefits of physical activity (Dergance et al., 2003). Recent qualitative research suggesting that safety and community support (Wilbur, Chandler, Dancy, Choi, & Plonczynski, 2002), family or cultural responsibilities (Young, He, Harris, & Mabry, 2002), or lack of facilities or prohibitive costs (Evenson, Sarmiento, Macon, Tawney, & Ammerman, 2002) are the major reasons for high levels of inactivity among African American and Latina women. The latter findings do not suggest dissimilar attitudes about physical activity as a powerful source of the differences in activity witnessed between different cultural groups. Yet, other research would indicate that cultural attitudes are in fact a potentially strong source of influence. Research that can directly compare attitudes about the desirability of physical activity outcomes appears to be rare as most studies appear to focus on comparing perceived benefits of physical activity across cultural or ethnic groups. Also, few studies have examined subjective norms in this fashion. Only by understanding how attitudes and norms differ between cultures can efforts to persuade these groups to be physically active be successful. In a study of over 2100 eighth-grade female students from South Carolina (Trost et al., 2002), White participants reported more favorable attitudes regarding exercise and indicated greater social pressure to engage in exercise (subjective norm). Anecdotal evidence would suggest that participating in sport or exercise programs may be seen as breaking a cultural norm. The Native-American winner of the gold medal in the 10,000 meter race in the 1964 Olympics, Billy Mills, explains that becoming immersed in sport programs away from the reservation is “like walking in death…If you go too far into [Anglo] society, there’s a fear of losing your Indianness. There’s a spiritual factor that comes into play. To become part of white society you give up half your soul” (Simpson, 1996 as cited in Coakley, 1998, p. 270). Determining how culture impacts attitudes and social norms for physical activity participation should be an important objective for exercise psychologists in the coming decade. Attitudes and Cognitive Dissonance Attitude change is often achieved through persuasion, yet sometimes attitudes change because of people’s behavior. People want to view the world in a consistent manner not only with respect to their attitudes, but also with respect to their actions. Therefore, because many people in the United States are sedentary, it is likely that their attitudes about physical activity have changed to become congruent with their actions (or inaction). Sedentary individuals may actually change their attitude about physical activity making it less valued so that they feel they are consistent and not hypocritical. When people recognize that their attitudes and behaviors are inconsistent with one another, they tend to experience psychological discomfort which is called cognitive dissonance. Experiencing this discomfort motivates people to change either their attitudes or actions to achieve consistency (Festinger, 1957). Though dissonance theory has not been used extensively in physical activity contexts, there have been a few intriguing studies in related areas. In a study focusing on weight loss, Axsom and Cooper (1985) recruited a group of moderately overweight young women for a study described as an “Experiment concerning possible methods of weight reduction.” All of the participants were told that there was recent evidence that “neurophysiological arousal” could lead to weight loss. One group of participants was assigned to the high effort condition in which the cognitive and perceptual tasks that were supposed to elicit the “neurophysiological arousal” were very demanding and difficult. Another group of participants was assigned to the low effort condition in which the tasks were actually quite easy and relaxing. Both groups were given a booklet in which to monitor their eating patterns over the three week course of the study, but there was no other information offered on effective weight loss regimens. Finally, 10 participants were assigned to a control group in which they simply came to the research center to be weighed, and performed no other tasks. Participants in the high effort condition lost 1.76 lbs during the three weeks of the experiment, while the low effort group lost 0.82 lbs and the control group gained 0.18 lbs. While these data showed a significant effect of the effort manipulation after three weeks, a truly dramatic difference emerged after six months, when the high effort group had lost an average of 8.55 lbs while the low effort group returned to their original weight and the control group had gained almost a pound. It would be tempting to think that Axsom and Cooper had discovered a terrific new method for weight loss, but there is no known scientific reason why the cognitive and perceptual tasks would induce weight loss, especially when the tasks were never performed during the five months after the experimental sessions were concluded. Instead, Axsom and Cooper argue that high effort participants had to justify the effort they were voluntarily expending in the experiment, and that they did so by placing greater value on the goal of weight loss, thereby reducing the cognitive dissonance they experienced. The internal dialogue may have been something like: “Why am I working so hard in this experiment? I don’t work this hard without a really good reason. It must be that I really want to lose weight.” Once the value of losing weight had been increased, in the weeks and months following the experiment participants from the high effort group could employ whatever weight loss program they wished in order to achieve that goal. Participants in the low effort condition did not have to go through the effort justification process and therefore did not place increased value on weight loss. The process of dissonance reduction leading to enhancement of the value of weight loss by the high effort participants produced a very durable effect. In a one-year followup they had maintained almost all of the six month weight loss (6.78 lbs) while the low effort participants remained within a pound of their baseline weight. Another example of how cognitive dissonance can lead to behavior change is the “self-prophecy effect” (Spangenberg & Greenwald, 2001). Studies focusing on a number of different behaviors have shown that the simple act of predicting one’s own behavior in the future can lead to significant changes in the frequency or intensity of the target behavior. Of most relevance to physical activity behavior, Spangenberg (1997) contacted health club members who had not used the club facilities for at least one month. He simply asked them to predict how frequently they would use the club in the future. Another group who met the same criteria for nonuse of the club were identified but not contacted. The number of visits to the health club over the next six months was recorded for both groups. The self-prophecy group, who had made a prediction about their use of the club visited it twice as frequently as the control group. Having made a prediction about a desirable future behavior, failure to use the club at that level would be dissonant with the knowledge of what one had predicted, and dissonance was reduced or avoided by actually using the club more frequently. The subtle, but powerful motivation for consistency between attitudes and behavior can be used to facilitate desired behavioral changes. Conclusions Clearly, pressures exerted by others influence many of the choices we make in life in addition to the actions we pursue – including engaging in physical activities. We are more likely to engage in physical activities if we perceive that others engage in these activities and if we have favorable attitudes about physical activity. It is most important for the potential exerciser to perceive that others actually engage in the behavior for meaningful relationships to exist between social norms and exercise behavior. Believing that others feel you should exercise, in contrast, only appears to relate to exercise participation in particular situations. Unfortunately, it may be easier to manipulate injunctive/ought norms than descriptive/actual norms. Thus, the exercise professional has limited options in this regard save perhaps making friends’ participation more salient to clients. Fortunately, there are other types of social influence that can be used to foster physical activity. To successfully influence others to exercise, it may be possible to use dissonance to one’s advantage. Simple techniques like having clients predict their usage of a fitness facility or incorporating a very difficult initiation process to a fitness group may cause dissonance if the client is not exercising regularly. This in turn may elicit increased participation to achieve balance. It is also possible to directly persuade individuals that exercise is a worthwhile activity. Persuasive messages will be more influential if delivered by well-liked experts, who are seen as trustworthy. Research shows that mass media approaches are not very effective for persuading people to be physically active, but localized approaches using print media and individual contacts have documented, positive effects in this regard. III. SOCIAL SUPPORT People do not exercise merely to look good in other’s eyes or because we have been persuaded by others to do so, sometimes people exercise because they obtain social benefits from physical activity participation. Social support has been defined in many different ways, but a general definition has been identified by Wallston, Alagna, DeVellis, and DeVellis (1983) as reassurance or assistance, or information or feedback one obtains through contact with other individuals or groups. Frequency or type of social contacts may have a strong influence on well-being. For example, the frequency of retired individuals’ interactions with others predicts life satisfaction (Dorfman, Kohout, & Heckert, 1985). Yet, the quality of social contact or interaction may also be important to consider (Aquino, Russell, Cutrona, & Altmaier, 1996). In physical activity contexts, social support research has often followed Weiss’s (1974) theoretical framework specifying six different social provisions that might be obtained from social contacts and thought to be social support. These six provisions are: a) Reassurance of worth or the provision of positive feedback from others that boosts one’s sense of self-esteem, b) Social integration or a sense of belonging to a group with common interests and goals, c) Attachment or the ability to find emotional support from others, d) Reliable alliance or an assurance that actual assistance or aid can be obtained from others if necessary, e) Guidance or advice or information from others, and f) Opportunity for nurturance or the ability to help others, which in turn builds a personal sense of competence. Research in physical activity settings has generally supported Weiss’s (1974) framework, and found that social support has mostly a positive effect on physical activity participation. Duncan, McAuley, Stoolmiller, and Duncan (1993) found that reassurance of worth, attachment, and guidance were related to attendance in a structured exercise program. Feelings of worth and the ability to find attachment were positively related to adherence. Individuals who perceived a high degree of guidance, however, did not adhere as well at times. Duncan, Duncan, and McAuley (1993) found that guidance and reassurance of worth discriminated between female adherers and nonadherers to an exercise program, while guidance and social integration discriminated for males. Interestingly, female adherers showed higher levels of social support (guidance, worth, integration, attachment, and nurturance) than female nonadherers, while for males only one dimension of social support (integration) was greater for adherers compared to nonadherers. These results are congruent with the conclusions of a literature review by Cross and Madson (1997), in which evidence was reviewed that indicates that women view themselves as being in relationships with others, while men view themselves as more independent. Baumeister and Sommer (1997) in a commentary on the Cross and Madson review point out that women’s social behaviors are directed at establishing and maintaining close dyadic relationships, while men are oriented toward a larger social sphere. The finding that men who adhere to an exercise regimen perceive higher levels of integration than men who do not adhere is very consistent with this formulation. The specific kinds of social support provided in a given setting may determine whether it will be more or less effective for men than for women. Research has shown that social support is a distinct entity with effects independent of subjective norm and social cohesion (Courneya & McAuley, 1995). Meta-analysis has shown that adherence is usually improved when individuals exercise in groups (ES = 0.32; Carron, Hausenblas, & Mack, 1996). In addition, people who exercise in groups may experience more positive mood states associated with participation compared to those who exercise alone (Gauvin & Rejeski, 1993). The exercise leader may be a particularly important source of social support in exercise settings. Franklin (1988) states that the exercise leader may be the “single most” important influence on exercise adherence. Though research is somewhat lacking in this area, Carron and colleagues found a small to moderate effect (ES = .31) for the influence of exercise leaders on behavior. Carron, Hausenblas, and Estabrooks (1999) note, however, that most of this type of research does not compare good vs. poor exercise leaders; rather, they compare good vs. normal exercise leaders (who may be quite good). Therefore, the importance of the exercise leader should not be underestimated. Social support from family and friends may also be a very important factor in maintaining higher levels of physical activity. Carron et al.’s (1996) review found a moderate size effect (ES = .69) for family influences on exercise compliance behavior. Wallace, Raglin, and Jastremski (1995) found that married individuals who joined an exercise program with their spouse were more likely to attend regularly and less likely to drop out compared to individuals who did not join with their spouse. Results from Chogahara (1999) in fact indicate that positive social influences from family and friends have a stronger relationship to leisure-time energy expenditure than positive influences from experts. Conclusions As a whole, physical activity participation appears to be fostered when there is a socially supportive atmosphere or when participants perceive social support when striving for their exercise goals. On the basis of existing research, exercise professionals should ensure that exercise participants are able to get feedback from others that boosts their self-esteem, have the opportunity to find a group in which they feel comfortable, are supported emotionally and tangibly and are able to obtain useful guidance or advice from other exercisers, friends, family, or exercise leaders. The opportunity to provide nurturance appears less important for achieving consistent physical activity participation. Exercise professionals should also consider that male and female participants will be more successful upon receiving different types of social support. It appears that emotional support is more important for females, while group identification is more important for males (Duncan, Duncan et al., 1993). IV. COHESION While social support refers to resources or feelings of worth that we may get from others around us, cohesion refers to the tendency of one’s group to stick together and remain united in the pursuit of similar goals (Carron, 1982). Cohesion may take the form of interpersonal liking or social cohesion, or a unity of commitment to a common goal or task cohesion. Often, cohesion has been believed to have an effect on group performance. Management teams, for example, often attempt to form cohesive work teams as an attempt to boost productivity. Stogdill (1972) found, however, that cohesion can have a negative, positive, or no effect on performance depending on the norm for productivity. Essentially, a cohesive group with low standards will underachieve, while a cohesive group with high standards will overachieve. Interestingly, the interaction between norms and cohesion has yet to be investigated in exercise and physical activity contexts. The majority of research concerning the effects of cohesion in physical activity settings has examined how cohesion affects adherence to group exercise. Overall, the results appear very encouraging. Reviewing six studies, Carron et al. (1996) found a moderate size effect (ES = .62) for task cohesion on adherence behavior. The effect for social cohesion, based on four studies, was only of a small magnitude (ES = .25). It appears that a shared commitment in exercise groups to achieving common goals is more effective than interpersonal liking for enhancing adherence. It is surprising that social cohesion does not demonstrate a somewhat larger effect considering its status as a fundamental psychological need for achieving satisfaction (Sheldon et al., 2001), and its essential role for achieving intrinsic motivation (Deci & Ryan, 1995), which appears to be very important for sustained exercise participation (Li, 1999; Oman & McAuley, 1993). Nonetheless, social cohesion does appear to influence adherence, though somewhat less than task cohesion. Spink and Carron (1994) examined the effects of cohesion on adherence to 13-week exercise programs in university and private fitness club settings. In both cases, lower perceptions of cohesion were related to dropping out of the program, though task cohesion had a stronger influence in the university setting while social cohesion had a stronger influence in the fitness club setting. In addition to dropout rate, lower levels of perceived cohesion have been shown to relate to increased absenteeism and tardiness (Spink & Carron, 1992). Other studies have found that cohesion relates to exercise participation in a clinical exercise setting (Fraser & Spink, 2002), among older adults (Estabrooks & Carron, 1999), and among adult participants at a fitness center (Annesi, 1999). In an attempt to determine if an intervention designed to promote cohesion could improve program adherence, Carron and Spink (1993) conducted a study using 17 university aerobics classes that met for 13 weeks. Nine were taught using a traditional approach, and eight included a team building intervention. Near the end of the program, participants in the experimental group reported higher levels of task cohesion (individual attraction to the group task) and satisfaction with the exercise program. Measures of attendance, however, were not reported. Annesi (1999) was able to show improvement in both cohesion and attendance, and a lower dropout rate using a 5-7 minute team building warm-up period before exercise sessions at a fitness center.  Cohesion may also be associated with improved feeling states associated with exercise participation. Though not many studies have assessed this possibility directly, Courneya (1995) found correlations between cohesion and positive mood states. Gauvin and Rejeski (1993) did not assess cohesion, but did find that participants exercising in group settings experienced more positive feeling states in comparison to those who exercised in more solitary settings.  Research concerning the effect of cohesion on physical activity participation and associated psychological outcomes is relatively sparse. Yet, among the studies that have been completed in this area, most show positive effects. Additionally, prospective, theory-based studies have provided confirmation of this relationship (Carron & Spink, 1993; Spink & Carron, 1994). Task cohesion appears to have a stronger positive relation to participation than does social cohesion. Cohesion may also influence our feeling states in response to exercise. However, research examining affect and transient mood states as they may be associated with different types of cohesion is necessary before firm conclusions can be made in this respect. Based on these findings, exercise professionals should make attempts to foster cohesion within their client groups. Exactly how to best promote cohesion in such settings is not yet known, but Carron and Spink’s (1993) methodology yielded positive effects by promoting group distinctiveness, keeping exercisers in stable locations during exercise, establishing group goals, asking sacrifices of group members, and promoting interaction and communication among group members. V. CONCLUSIONS Social factors are critical influences upon our choices to adopt or maintain physical activity pursuits. The theories and research documented in this chapter show that our physical activity choices are influenced by messages we receive from others about physical activity, our desire to project a positive image to others and adhere to social norms, our desire to feel that our actions and attitudes are congruent with one another, and our desire to feel social connection with others in our daily pursuits. Ultimately, to influence people to become more physically active, messages from experts and public service announcements won’t have much impact if the social influences affecting the target populations don’t support changes in physical activity. The literature in social psychology has much to offer exercise professionals concerning how people respond to and are affected by social forces. Exercise professionals should base their attempts to change the behavior of their clients on sound scientific research – even if that research has not focused specifically on physical activity as the dependent variable. It is our strong belief that exercise professionals should do more than simply advocate for physical activity and its health benefits. Of course, you are highly credible communicators, and your advocacy will have some impact on potential clients and exercisers. However, you can also make use of the principles of social influence to affect the adoption and maintenance of effective levels of physical activity by target groups. Apply the principles we have outlined in this chapter as you design exercise programs, or as you work with clients enrolled in existing programs. If you need additional help, consult with social psychology faculty members and other social influence experts at a nearby college or university, as well as with exercise science faculty. Bringing well designed social influence attempts to bear on groups who can benefit from increased levels of physical activity will increase your impact on public health. If one of your professional goals is to be more effective in getting more people to be more active more often, use the principles of social influence to help you achieve that goal. References Ajzen, I., & Madden, T. J. (1986). Prediction of goal-directed behavior: Attitudes, intentions, and perceived behavioral control. Journal of Experimental Social Psychology, 22(5), 453-474. Allen, M. E., & Coen, D. (1987). Naloxone blocking of running-induced mood changes. Annals of Sports Medicine, 3(3), 190-195. Annesi, J. J. (1999). Effects of minimal group promotion on cohesion and exercise adherence. Small Group Research, 30(5), 542-557. Aquino, J. A., Russell, D. W., Cutrona, C. E., & Altmaier, E. M. (1996). Employment status, social support, and life satisfaction among the elderly. Journal of Counseling Psychology, 43(4), 480-489. Arkin, R. M. (1981). Self-presentational styles. In J. T. Tedeschi (Ed.), Impression management theory and social psychological research (pp. 331-333). New York, NY: Academic Press. Association, A. P. (1994). Diagnostic and statistical manual of mental disorders (3rd ed.). Washington, DC: Author. Axsom, D., & Cooper, J. (1985). Cognitive dissonance and psychotherapy: The role of effort justification in inducing weight loss. Journal of Experimental Social Psychology, 21(2), 149-160. Baumeister, R. F. (1982). A self-presentational view of social phenomena. Psychological Bulletin, 91, 3-26. Baumeister, R. F., & Sommer, K. L. (1997). What do men want? Gender differences and two spheres of belongingness: Comment on Cross and Madson (1997). Psychological Bulletin, 122(1), 38-44. Blumenthal, J. A., O'Toole, L. C., & Chang, J. L. (1984). Is running an analogue of anorexia nervosa? An empirical study of obligatory running and anorexia nervosa. Journal of the American Medical Association, 252(4), 520-523. Brehm, J. W. (1966). A Theory of Psychological Reactance. Oxford, England: Academic Press. Carron, A. V. (1982). Cohesiveness in sport groups: Interpretations and considerations. Journal of Sport Psychology, 4(2), 123-138. Carron, A. V., Hausenblas, H. A., & Estabrooks, P. A. (1999). Social influence and exercise involvement. In S. Bull (Ed.), Adherence issues in sport and exercise. West Sussex, England: John Wiley & Sons. Carron, A. V., Hausenblas, H. A., & Mack, D. (1996). Social influence and exercise: A meta-analysis. Journal of Sport and Exercise Psychology, 18(1), 1-16. Carron, A. V., & Spink, K. S. (1993). Team building in an exercise setting. Sport Psychologist, 7(1), 8-18. Cash, T. F., Novy, P. L., & Grant, J. R. (1994). Why do women exercise? Factor analysis and further validation of the Reasons for Exercise Inventory. Perceptual and Motor Skills, 78(2), 539-544. Chatzisarantis, N. L. D., & Biddle, S. J. H. (1998). Functional significance of psychological variables that are included in the theory of planned behaviour: A self-determination theory approach to the study of attitudes, subjective norms, perceptions of control and intentions. European Journal of Social Psychology, 28(3), 303-322. Chogahara, M. (1999). A multidimensional scale for assessing positive and negative social influences on physical activity in older adults. J Gerontol B Psychol Sci Soc Sci. Coakely, J. J. (1998). Sport in society: Issues and controversies. Boston, MA: McGraw-Hill. Coen, S. P., & Ogles, B. M. (1993). Psychological characteristics of the obligatory runner: A critical examination of the anorexia analogue hypothesis. Journal of Sport and Exercise Psychology, 15(3), 338-354. Conroy, D. E., Motl, R. W., & Hall, E. G. (2000). Progress toward construct validation of the Self-Presentation in Exercise Questionnaire (SPEQ). Journal of Sport and Exercise Psychology, 22(1), 21-38. Courneya, K. S. (1995). Cohesion correlates with affect in structured exercise classes. Perceptual and Motor Skills, 81(3, Pt 1), 1021-1022. Courneya, K. S., & McAuley, E. (1995). Reliability and discriminant validity of subjective norm, social support, and cohesion in an exercise setting. Journal of Sport and Exercise Psychology, 17(3), 325-337. Courneya, K. S., Plotnikoff, R. C., Hotz, S. B., & Birkett, N. J. (2000). Social support and the theory of planned behavior in the exercise domain. American Journal of Health Behavior, 24(4), 300-308. Crawford, S., & Eklund, R. C. (1994). Social physique anxiety, reasons for exercise, and attitudes toward exercise settings. Journal of Sport and Exercise Psychology, 16(1), 70-82. Cross, S. E., & Madson, L. (1997). Models of the self: Self-construals and gender. Psychological Bulletin, 122(1), 5-37. Davis, C., Fox, J., Brewer, H., & Ratusny, D. (1995). Motivations to exercise as a function of personality characteristics, age, and gender. Personality and Individual Differences, 19(2), 165-174. De Bourdeaudhuij, I., & Sallis, J. (2002). Relative contribution of psychosocial variables to the explanation of physical activity in three population-based adult samples. Preventive Medicine, 34, 279-288. Deci, E. L., & Ryan, R. M. (1995). Human agency: The basis for true self-esteem. In M. Kernis (Ed.), Efficacy, agency, and self-esteem (pp. 31-49). New York, NY: Plenum. Dergance, J. M., Calmbach, W. L., Dhanda, R., Miles, T. P., Hazuda, H. P., & Mouton, C. P. (2003). Barriers to and benefits of leisure time physical activity in the elderly: differences across cultures. Journal of the AMerican Geriatric Society, 51(6), 863-868. Diehl, N. S., Johnson, C. E., Rogers, R. L., & Petrie, T. A. (1998). Social physique anxiety and disordered eating: what's the connection? Addictive Behavior, 23(1), 1-6. Doherty, K., & Schlenker, B. R. (1991). Self-consciousness and strategic self-presentation. Journal of Personality, 59(1), 1-18. Donovan, R. J., & Robinson, L. (1992). Using mass media in health promotion: The Western Australia immunisation campaign. In R. Hall & J. Richter (Eds.), Immunisation: The old and the new. Canberra: Public Health Association. Dorfman, L. T., Kohout, F. J., & Heckert, D. A. (1985). Retirement satisfaction in the rural elderly. Research on Aging, 7(4), 577-599. Duncan, T. E., Duncan, S. C., & McAuley, E. (1993). The role of domain and gender-specific provisions of social relations in adherence to a prescribed exercise regimen. Journal of Sport and Exercise Psychology, 15(2), 220-231. Duncan, T. E., McAuley, E., Stoolmiller, M., & Duncan, S. C. (1993). Serial fluctuations in exercise behavior as a function of social support and efficacy cognitions. Journal of Applied Social Psychology, 23(18), 1498-1522. Eagly, A. H., Wood, W., & Chaiken, S. (1978). Causal inferences about communicators and their effect on opinion change. Journal of Personality and Social Psychology, 36(4), 424-435. Eklund, R. C., & Crawford, S. (1994). Active women, social physique anxiety, and exercise. Journal of Sport and Exercise Psychology, 16(4), 431-448. Estabrooks, P. A., & Carron, A. V. (1999). Group cohesion in older adult exercisers: Prediction and intervention effects. Journal of Behavioral Medicine, 22(6), 575-588. Evenson, K. R., Sarmiento, O. L., Macon, M. L., Tawney, K. W., & Ammerman, A. S. (2002). Environmental, policy, and cultural factors related to physical activity among Latina immigrants. Women and Health, 36(2), 43-57. Feingold, A. (1992). Good-looking people are not what we think. Psychological Bulletin, 111(2), 304-341. Festinger, L. (1957). A theory of cognitive dissonance: Oxford, England: Row, Peterson. (1957). Frank Abagnale - New Life. (1998). Retrieved December 15, 2003 from http://www.abc.net.au/rn/talks/lm/stories/s111098.htm Franklin, B. A. (1988). Exercise programming for the moderately obese adult: Rationale and procedures. In K. L. Clark & R. B. Parr (Eds.), Evaluation and management of eating disorders: Anorexia, bulimia, and obesity. La Crosse exercise and health series (pp. 129-143). Champaign, IL: Life Enhancement Publications. Fraser, S. N., & Spink, K. S. (2002). Examining the role of social support and group cohesion in exercise compliance. Journal of Behavioral Medicine, 25(3), 233-249. Frederick, C. M., Morrison, C., & Manning, T. (1996). Motivation to participate, exercise affect, and outcome behaviors toward physical activity. Perceptual and Motor Skills, 82(2), 691-701. Gauvin, L., & Rejeski, W. J. (1993). The Exercise-Induced Feeling Inventory: Development and initial validation. Journal of Sport and Exercise Psychology, 15(4), 403-423. Godin, G., & Kok, G. (1996). The theory of planned behavior: A review of its applications to health-related behaviors. American Journal of Health Promotion, 11(2), 87-98. Gulker, M. G., Laskis, T. A., & Kuba, S. A. (2001). Do excessive exercisers have a higher rate of obsessive-compulsive symptomatology? Psychology, Health and Medicine, 6(4), 387-398. Hardy, C. J. (1990). Social loafing: Motivational losses in collective performance. International Journal of Sport Psychology, 21(4), 305-327. Hart, E. A., Leary, M. R., & Rejeski, W. J. (1989). The measurement of social physique anxiety. Journal of Sport and Exercise Psychology, 11(1), 94-104. Hauck, E. R., & Blumenthal, J. A. (1992). Obsessive and compulsive traits in athletes. Sports Medicine, 14(4), 215-227. Hausenblas, H. A., Carron, A. V., & Mack, D. E. (1997). Application of the theories of reasoned action and planned behavior to exercise behavior: A meta-analysis. Journal of Sport and Exercise Psychology, 19(1), 36-51. Hausenblas, H. A., & Fallon, E. A. (2002). Relationship among body image, exercise behavior, and exercise dependence symptoms. International Journal of Eating Disorders, 32(2), 179-185. Heider, F. (1958). The psychology of interpersonal relations: Oxford, England: Wiley. (1958). Henderson, K. A., & Ainsworth, B. E. (2001). Physical activity and human development among older Native American women. Journal of Aging and Physical Activity, 9(3), 285-299. Imm, P. S., & Pruitt, J. (1991). Body shape satisfaction in female exercisers and nonexercisers. Women and Health, 17(4), 87-96. Jones, D. A., Ainsworth, B. E., Croft, J. B., Macera, C. A., Lloyd, E. E., & Yusef, H. R. (1998). Moderate leisure-time physical activity: Who is meeting the public health recommendations? A national cross-sectional study. Archives of Family Medicine, 7, 285-289. Kenrick, D., T., Neuberg, S., L., & Cialdini, R. B. (1999). Social Psychology: Unraveling the Mystery. Needham Heights, MA: Allyn and Bacon. Keski-Rahkonen, A. (2001). Exercise dependence-A myth or a real issue? European Eating Disorders Review, 9(4), 279-283. Kotler, P., & Roberto, E., L. (1989). Social Marketing - Strategies for Changing Public Behavior. New York, NY: The Free Press, a division of Macmillan, Inc. Kowalski, N. P., Crocker, P. R., & Kowalski, N. P. (2001). Physical self and physical activity relationships in college women: does social physique anxiety moderate effects? Research Quarterly for Exercise and Sport, 72(1), 55-62. Krane, V., Stiles-Shipley, J. A., Waldron, J., & Michalenok, J. (2001). Relationships among body satisfaction, social physique anxiety, and eating behaviors in female athletes and exercisers. Journal of Sport Behavior, 24(3), 247-264. Lantz, C. D., Hardy, C. J., & Ainsworth, B. E. (1997). Social physique anxiety and perceived exercise behavior. Journal of Sport Behavior, 20(1), 83-93. Leary, M. R. (1995). Self-presentation: Impression management and interpersonal behavior. Madison, WI: Brown & Benchmark. Leary, M. R., Barnes, B. D., & Griebel, C. (1986). Cognitive, affective, and attributional effects of potential threats to self-esteem. Journal of Social and Clinical Psychology, 4(4), 461-474. Leary, M. R., Tchividjian, L. R., & Kraxberger, B. E. (1994). Self-presentation can be hazardous to your health: Impression management and health risk. Health Psychology, 13, 461-470. Leventhal, H., Watts, J. C., & Pagano, F. (1967). Effects of fear and instructions on how to cope with danger. Journal of Personality and Social Psychology, 6(3), 313-321. Lewis, B. P., & Linder, D. E. (1994). The social perceptions of athletes and sport preference: You are what you play. Paper presented at the American Psychological Association, Los Angeles, CA. Li, F. (1999). The Exercise Motivation Scale: Its multifaceted structure and construct validity. Journal of Applied Sport Psychology, 11(1), 97-115. Marcus, B. H., Owen, N., Forsyth, L. H., Cavill, N. A., & Fridinger, F. (1998). Physical activity interventions using mass media, print media, and information technology. American Journal of Preventive Medicine, 15(4), 362-378. Mondin, G. W., Morgan, W. P., Piering, P. N., Stegner, A. J., & et al. (1996). Psychological consequences of exercise deprivation in habitual exercisers. Medicine and Science in Sports and Exercise, 28(9), 1199-1203. Okun, M. A., Karoly, P., & Lutz, R. (2002). Clarifying the contribution of subjective norm to predicting leisure-time exercise. American Journal of Health Behavior, 26(4), 296-305. Oman, R. F., & McAuley, E. (1993). Intrinsic motivation and exercise behavior. Journal of Health Education, 24(4), 232-238. Owen, P. R., & Laurel Seller, E. (2000). Weight and shape ideals: Thin is dangerously in. Journal of Applied Social Psychology, 30(5), 979-990. Paffenbarger, R. S., Jr., Hyde, R. T., Wing, A. L., Lee, I. M., & Kampert, J. B. (1994). Some interrelations of physical activity, physiological fitness, health, and longevity. In C. Bouchard & R. J. Shephard (Eds.), Physical activity, fitness, and health: International proceedings and consensus statement (pp. 119-133). Champaign, IL, England: Human Kinetics Publishers. Perloff, R. M. (1993). The dynamics of persuasion. Hillsdale, NJ, England: Lawrence Erlbaum Associates, Inc. Petty, R. E., & Cacioppo, J. T. (1986). Communication and persuasion: Central and peripheral routes to attitude change. New York, NY: Springer-Verlag. Phillips, W. T., Kiernan, M., & King, A. C. (2001). Part II. Crosscutting issues. In A. Baum & T. A. Revenson (Eds.), Handbook of health psychology (pp. 321-657). Mahwah, NJ: Lawrence Erlbaum Associates, Publishers. Pierce, E. F. (1994). Exercise dependence syndrome in runners. Sports Medicine, 18(3), 149-155. Pomerantz, E. M., Chaiken, S., & Tordesillas, R. S. (1995). Attitude strength and resistance processes. Journal of Personality and Social Psychology, 69(3), 408-419. Reno, R. R., Cialdini, R. B., & Kallgren, C. A. (1993). The transsituational influence of social norms. Journal of Personality and Social Psychology, 64(1), 104-112. Rodgers, W. M., Hall, C. R., Blanchard, C. M., & Munroe, K. J. (2001). Prediction of obligatory exercise by exercise-related imagery. Psychology of Addictive Behaviors, 15(2), 152-154. Sadalla, E. K., Linder, D. E., & Jenkins, B. A. (1988). Sport preference: A self-presentational analysis. Journal of Sport and Exercise Psychology, 10(2), 214-222. Services, U. S. D. o. H. H. (1996). Physical activity and health: A report of the Surgeon General. Atlanta, GA: Centers for Disease Control. Sheeran, P., & Orbell, S. (2000). Self-schemas and the theory of planned behaviour. European Journal of Social Psychology, 30(4), 533-550. Sheldon, K. M., Elliot, A. J., Kim, Y., & Kasser, T. (2001). What is satisfying about satisfying events? Testing 10 candidate psychological needs. Journal of Personality and Social Psychology, 80(2), 325-339. Simpson, K. (1996). Sporting dreams die on the "rez." In D. S. Eitzen (Ed.), Sport in contemporary society. New York, NY: St. Martin's Press. Spangenberg, E. R. (1997). Increasing health club attendance through self-prophecy. Marketing Letters, 8, 23-32. Spangenberg, E. R., & Greenwald, A. G. (2001). Self-prophecy as a behavior modification technique in the United States. In W. Wosinska & R. B. Cialdini (Eds.), The practice of social influence in multiple cultures. Applied social research (pp. 51-62). Mahwah, NJ: Lawrence Erlbaum Associates, Publishers. Spink, K. S. (1992). Relation of anxiety about social physique to location of participation in physical activity. Perceptual and Motor Skills, 74(3, Pt 2), Spec Issue, 1075-1078. Spink, K. S., & Carron, A. V. (1992). Group cohesion and adherence in exercise classes. Journal of Sport and Exercise Psychology, 14, 78-86. Spink, K. S., & Carron, A. V. (1994). Group cohesion effects in exercise classes. Small Group Research, 25(1), 26-42. Stevens, L. E., & Fiske, S. T. (1995). Motivation and cognition in social life: A social survival perspective. Social Cognition, 13(3), 189-214. Stogdill, R. M. (1972). Group productivity, drive, and cohesiveness. Organizational Behavior and Human Decision Processes. Strauss, B. (2002). Social facilitation in motor tasks: A review of research and theory. Psychology of Sport and Exercise, 3(3), 237-256. Tice, D. M. (1991). Esteem protection or enhancement? Self-handicapping motives and attributions differ by trait self-esteem. Journal of Personality and Social Psychology, 60, 711-725. Treasure, D. C., Lox, C. L., & Lawton, B. R. (1998). Determinants of physical activity in a sedentary, obese female population. Journal of Sport and Exercise Psychology, 20(2), 218-224. Trost, S. G., Pate, R. R., Dowda, M., Ward, D. S., Felton, G., & Saunders, R. (2002). Psychosocial correlates of physical activity in White and African-American girls. Journal of Adolescent Health, 31(3), 226-233. Wallace, J. P., Raglin, J. S., & Jastremski, C. (1995). Twelve month adherence of adults who joined a fitness program with a spouse vs. without a spouse. Journal of Sports Medicine and Physical Fitness, 35, 206-213. Wallston, B. S., Alagna, S. W., DeVellis, B. M., & DeVellis, R. F. (1983). Social support and physical health. Health Psychology, 2(4), 367-391. Weinstein, H. M., & Richman, A. (1984). The group treatment of bulimia. Journal of American College Health, 32(5), 208-215. Weiss, R. S. (1974). The provisions of social relationships. In Z. Rubin (Ed.), Doing unto others (pp. 17-26). Englewood Cliffs, NJ: Prentice-Hall. Wilbur, J., Chandler, P., Dancy, B., Choi, J., & Plonczynski, D. (2002). Environmental, policy, and cultural factors related to physical activity in urban, African American women. Women and Health, 36(2), 17-28. Williams, K. D., Nida, S. A., Baca, L. D., & Latane, B. (1989). Social loafing and swimming: Effects of identifiability on individual and relay performance of intercollegiate swimmers. Basic and Applied Social Psychology, 10(1), 73-81. Worringham, C. J., & Messick, D. M. (1983). Social facilitation of running: An unobtrusive study. Journal of Social Psychology, 121(1), 23-29. Yates, A., Shisslak, C. M., Allender, J., Crago, M., & Leehey, K. (1992). Comparing obligatory to nonobligatory runners. Psychosomatics: Journal of Consultation Liasion Psychiatry, 33(2), 180-189. Young, D. R., He, X., Harris, J., & Mabry, I. (2002). Environmental, policy, and cultural factors related to physical activity in well-educated urban African American women. Women and Health, 36(2), 29-41. Zajonc, R. B. (1965). Social facilitation. Science, 149, 269-274.