Reasons for Exercise and Motivation for Losing Weight:
Differences as a Function of Gender and Dietary Restraint
Lenny R. Vartanian
The University of New South Wales
Christopher M. Wharton
Arizona State University
Erica B. Green
Reasons for Exercise and Motivation for Losing Weight:
Differences as a Function of Gender and Dietary Restraint
Exercise and weight management are important components of a healthy lifestyle, but for many individuals weight loss and exercise take on an unhealthy dynamic. Regular exercise has benefits for an individual’s overall health, mood, as well as weight management. Exercise improves muscle strength, combats chronic disease, improves cardiovascular health, and lowers blood pressure and cholesterol (e.g., Brown, Mishra, Lee, & Bauman, 2000; Haskell et al., 2007). Exercise can also improve an individual’s mood as it promotes better sleep;, reduces depression, stress, and anxiety (Prichard & Tiggemann, 2008);, and increases self-esteem and body esteem (REF[CW1]?). In addition, exercise can help individuals to reduce or manage their weight (Gillison, Standage, & Skevington, 2006) and thus exercise can benefit the individual bysubsequently aid in preventing obesity and related illnesses.
Despite the numerous physical and psychological benefits associated with exercise, there are also some negative outcomes associated with particular types of motivationmotivations to exercise. For example, individuals who exercise for appearance reasons, as opposed to health reasons, tend to have higher levels of disordered eating and body dissatisfaction, decreased self-esteem (Thome & Espelage, 2007), and decreased psychological well-being (Maltby & Day, 2001). In contrast, exercising for health/fitness and mood/enjoyment reasons have been associated with more positive effects such as increased body satisfaction, increased self-esteem (Strelan, Mehaffey, & Tiggemann, 2003), and overall psychological well-being (Maltby & Day, 2001). Individuals who report health reasons for exercise are also more likely to be successful at weight loss (Brink & Ferguson, 1998).
Just as an individual’s motivation for exercise can be associated with negative psychological outcomes, an individual’s motivation for dieting and losing weight can also can also be associated with negative outcomes as well. For example, dieting with the motivation toto change one’s appearance can have negative implicationsmay predispose the individual to , such as engaging in more extreme dieting strategies and eating disordered behaviors (e.g., excluding food groups, avoiding meals, using laxatives, and vomiting; Putterman & Linden, 2004). Individuals who dDieteding for health-related reasons, in contrast, is not associated with these engaged in more positive behaviorsnegative outcomes. Specifically, individuals who dieted for health reasons were less likely to use such extreme dieting techniques, were more likely not to relapsebetter maintained weight loss over time (?),, and experienced less body dissatisfaction and greater self-esteem. Thus, not all types of dieting behavior are equally beneficial or harmful (Putterman & Linden, 2004).
Gender differences have been observed in both the frequency of weight-loss attempts, and in the motives for attempting to lose weight. Overall, women are more likely to attempt to lose weight than are men (Serdula, Mokdad, Williamson, et al. 1999). Furthermore, researchers have found that women tend to exercise primarily for weight control, body tone, and attractiveness, whereas men are less likely to exercise for these reasons (Furnham & Calnan, 1998). As a result of motivational differences between women and men, women tend to experience fewer of the psychological benefits of exercise (Strelan et al., 2003). Another individual difference that might be relevant to exercise and weight-loss motives is dietary restraint. Restrained eaters are individuals who regularly attempt to restrict their food intake as a means of controlling their body shape (Herman & Polivy, 1980). Just as women are more focused on appearance motives for exercise and diet, we might expect restrained eaters to be highly motivated by appearance reasons[CW2].
One possible explanation for the observed gender differences in motivation to exercise and to lose weight can be found in Objectification Theory (Fredrickson, Roberts, Noll, Quinn, & Twenge, 1998). According to Objectification Theory, women in Westernized cultures are pressured to have thin and attractive bodies and come to believe that their bodies are sexual objects to be observed by others. Self-objectification occurs when individuals internalize the view that they are sexual objects and that they should be thin and sexually attractive. Self-objectification is associated with appearance anxiety, body dissatisfaction, reduced self-esteem and body esteem, restrained eating, and disordered eating (Strelan & Hargreaves, 2005). Given the cultural emphasis on appearance for women, young women tend to score higher than men on measures of self-objectification (Tiggemann & Lynch, 2001). A result of this self-objectification is that women are particularly motivated to exercise for appearance enhancement reasons, including exercising to manage their weight, improve body tone, and enhance their attractiveness (Strelan et al., 2003). In particular, Strelan et al. (2003) showed that the relationship between women’s self-objectification and their body esteem was mediated by appearance-related reasons for exercise. Although self-objectification and concern with one’s body is more frequently examined among women, men too are becoming increasingly concerned with their bodies (Parks & Read, 1997; Pope, Phillips, & Olivardia, 2000) and they are also turning to exercise to alleviate their concerns with being attractive (Strelan & Hargreaves, 2005).
A precursor to self-objectification is a more general internalization of societal standards of attractiveness (i.e., thinness for women and muscularity for men). Although most people are exposed to the same media images and societal pressures, not everyone internalizes those standards to the same degree (Thompson & Stice, 2001). Research has consistently shown that internalization of societal standards of attractiveness is related to body dissatisfaction, which in turn is related to disordered eating behavior among men and women (Keery, van den Berg, &
Thompson, 2004; Vartanian, 2009; Vartanian & Hopkinson, 2010). Other studies have shown a positive association between internalization and self-objectification among both men and women (Morry & Staska, 2001). No study to date, however, has examined the impact of internalization on people’s motivation to exercise and to lose weight.
The Present Study
The present study builds on past research by examining motivations for exercise and for losing weight as a function of both gender and dietary restraint. Although previous studies have considered individual differences in reasons for exercise and motivation for losing weight separately, none have examined both of these constructs simultaneously. Furthermore, we consider both gender and dietary restraint as individual differences that could influence exercise and weight-loss motives. Finally, we investigated the relation of reasons for exercise and motivation for losing weight with body dissatisfaction and drive for thinness, as well as the role of internalization of societal standards of attractiveness. Based on past research, we predicted that women in general (and dieters in particular) would be motivated to exercise and lose weight for appearance- based reasons more than for health-related reasons. We also predicted that motivation to lose weight and exercise for appearance-related reasons would be associated with more negative body image. Finally, we predicted that appearance motives to exercise and lose weight would mediate the link between internalization and body-image concerns.
Participants were 336 students (206 females, 130 males) at Syracuse University and at Arizona State University who completed a survey in exchange for course credit or for a chance to win a prize in a lottery drawing. Mean age was 22.8 years (SD = 7.85), and mean body mass index (BMI; kg/m2) was 23.9 (SD = 4.89). The majority of the sample was Caucasian (71%, n=238), 10% were Asian (n=35), 8% were Hispanic (n=27), 7% were African-American (n=25), and 3% indicated that they were “other” (n=11). Of those who reported their college affiliation, 35% (n=118) were first year students, 23% (n=77) were second year students, 15% (n=51) were third year students, 15% (n=50) were fourth year students, and 12% (n=39) were graduate students.
Measures and Procedure
Participants were recruited through undergraduate research participant pools and by mass e-mailings. They were invited to complete an online survey including the following measures:
Reasons for exercise. The Reasons for Exercise Inventory (Silberstein, Striegle-Moore, Timko, & Rodin, 1988) is a 24-item measure that assesses reasons for exercise in seven different domains (weight control, fitness, mood, health, attractiveness, enjoyment, and tone). Participants rated the importance of each reason for exercise (e.g., “To improve my appearance”) on a 7-point scale (1=Not at all important, 7= Extremely important). Following Strelan et al. (2003), the seven subscales were collapsed into three broader categories: appearance enhancement reasons (weight control, attractiveness, and tone; α = .83), health/fitness reasons (α = .89), and mood/enjoyment reasons (α = .80).
Motivation for losing weight. The Motivations for Weight Loss Questionnaire (Putterman & Linden, 2004) is a 30-item measure that assesses individuals’ motivation for dieting and losing weight. Each item is rated on a 5-point scale (1=Definitely disagree, 5=Definitely agree), and items are categorized into four subscales (appearance, health, social anxiety, and self-respect). For the purpose of this study, we include only the items related to appearance motives (α = .80) and health motives (α = .87) for losing weight.
Body image concerns. Two subscales of the Eating Disorder Inventory (EDI; Garner, Olmstead, & Polivy, 1983) were used to assess individuals’ concerns with body weight and shape: Body Dissatisfaction (EDI-BD; α = .90) and Drive for Thinness (EDI-DFT; α = .91). For both subscales, items were rated on a 6-point scale (1 = Never, 6 = Always), with higher scores indicating greater body dissatisfaction and greater drive for thinness. Because these two subscales were highly correlated (r = .72, p < .001), the scales were combined into a single index of body image concerns.
Dietary restraint. Participants also completed the Restraint Scale (Herman & Polivy, 1980), a 10-item self-report measure of dietary concerns, eating habits, and weight fluctuations. Higher scores indicated a greater degree of dietary restraint (α = .78). Individuals who scored 15 or higher on the Restraint Scale were classified as restrained eaters (n=108); individuals who scored 14 or lower were classified as unrestrained eaters (n=228).
Internalization of societal standards of attractiveness. The Sociocultural Attitudes Toward Appearance Questionnaire (SATAQ; Heinberg, Thompson, & Stormer, 1995) is a 14-item scale that assesses the degree to which people are aware of societal standards of attractiveness, as well as the extent to which individuals internalize those standards as self-relevant beliefs. The original scale was designed to assess these constructs among women (referring, for example, to “thin models in magazines”). An alternate version of the measure was created for male participants following the suggestion of Smolak, Levine, and Thompson (2001). For items that made specific reference to “thinness” or “thin women,” the wording was modified to refer to “muscularity” or “muscular” men. For the present study, only the 8 items of the internalization subscale were included. Each item was rated on a 7-point scale (1 = Completely disagree, 7 = Completely agree), and higher scores indicated a greater degree of internalization. Cronbach’s alphas were .91 for women and .78 for men.
Participants also provided some basic demographic information, including their age, height and weight, ethnicity, and college affiliation.
We first examined individual differences in reasons for exercise. Overall, health/fitness reasons for exercise received the highest level of endorsement (M = 5.73, SD = 1.05), followed by appearance reasons (M = 5.00, SD = 1.12), and mood/enjoyment reasons received the lowest level of endorsement (M = 4.41, SD = 1.20), ps < .001. To identify individual differences in reasons for exercise, we conducted a 3-way Analysis of Variance (ANOVA) with gender (male vs. female) and dietary restraint (restrained eaters vs. unrestrained eaters) as between-subjects factors, and reason for exercise (appearance vs. health/fitness vs. mood/enjoyment) as a within-subjects factor. The overall 3-way interaction was marginally significant, F (2, 325) = 2.92, p = .055. To further explore these effects, we conducted a series of 2-way (gender X restraint) ANOVAs separately for each reason for exercise (see Figure 1). For health- related reasons for exercise, there were no differences as a function of gender or dietary restraint, and there was also no interaction. For appearance reasons, there was a main effect of gender, with women more than men reporting appearance reasons for exercise, F (1, 326) = 12.45, p < .001. Similarly, restrained eaters reported exercising for appearance reasons more than did unrestrained eaters, F (1, 326) = 38.91, p < .001. There was no gender X restraint interaction. Finally, for mood/enjoyment reasons for exercise, there was only a marginally significant effect of gender (p = .083), with women tending to report more drive to exercise for mood/enjoyment than did men.
Next, we examined individual differences in motivation for losing weight. Overall, health motives for losing weight were rated higher (M = 3.31, SD = 1.17) than were appearance reasons for losing weight (M = 3.01, SD = 0.72), t (330) = 5.63, p < .001. To identify individual differences in motives for losing weight, we conducted a 3-way Analysis of Variance (ANOVA) with gender (male vs. female) and dietary restraint (restrained eaters vs. unrestrained eaters) as between-subjects factors and motivation for losing weight (health vs. appearance) as a within-subjects factor. The overall 3-way interaction was significant, F (1, 327) = 13.07, p < .001. To further explore these effects, we conducted a pair of 2-way (gender X restraint) ANOVAs separately for each motive for losing weight (see Figure 2). For health- related motives for losing weight, there was a main effect of gender[CW3]sex, F (1, 327) = 6.03, p = .02, a main effect of dietary restraint, F (1, 327) = 46.10, p < .001, and a gendersex by restraint interaction, F (1, 327) = 15.71, p < .001. Simple effects analysis revealed that female unrestrained eaters reported more motivation to lose weight for health reasons than did male unrestrained eaters (3.41 vs. 2.55), p < .001, whereas female and male restrained eaters did not differ in their motivation to lose weight for health reasons (3.80 vs. 4.00), p = .37. For appearance motives, there was a main effect of gender, with women reporting more motivation to lose weight for appearance reasons than did men, F (1, 329) = 12.73, p < .001. Similarly, restrained eaters reported more motivation to lose weight for appearance reasons than did unrestrained eaters, F (1, 329) = 124.56, p < .001. There was no gender by restraint interaction.
Table 1 shows the bivariate correlations among all of the variables in the present study (reasons for exercise, motivation for losing weight, body image concerns, internalization, and BMI). Body image concerns were positively correlated with appearance reasons for exercise, and there was a marginally significant negative correlation between body image concerns and health/fitness reasons for exercise. Similarly, internalization was positively correlated with appearance reasons for exercise, and negatively correlated with health/fitness reasons for exercise. Mood/enjoyment reasons for exercise were unrelated to both body image concerns and internalization. With respect to motives for losing weight, health and appearance motives were both positively correlated with body image concerns and internalization, but the correlations were stronger for appearance-based motives than for health-related motives. Finally, health reasons for exercise wereas positively correlated with health motives for losing weight, and appearance reasons for exercise was positively correlated with appearance motives for losing weight.
We conducted a pair of regression analyses to examine the impact of reasons for exercise and motivation for losing, separately, on body image concerns. First, we regressed body image concerns on the three reasons for exercise (health/fitness, appearance enhancement, and mood/enjoyment), BMI, and internalization. The overall model predicting body image concerns was significant, F (5, 310) = 61.67, p < .001, explaining 50% of the variance. Appearance reasons for exercise, internalization, and BMI were significant positive predictors of body image concerns, and health/fitness reasons for exercise wereas a significant negative predictor (see Table 2). Next, we regressed body image concerns on health motives for losing weight, appearance motives for losing weight, internalization, and BMI. The overall model predicting body image concerns was significant, F (4, 312) = 176.36, p < .001, explaining 69% of the variance. Appearance motives for losing weight, internalization, and BMI were all significant positive predictors of body image concerns (see Table 2).
Finally, we conducted a series of meditational analyses to determine whether appearance reasons for exercise and for losing weight mediated the association between internalization and body image concerns. Analyses were conducted using the steps outlined by Baron and Kenny (1986) and the SPSS macro provided by Preacher and Hayes (2004). In the first analysis, appearance reasons for exercise significantly mediated the association between internalization and body image concerns, Sobel’s Z = 5.58, p < .001, although the direct path remained highly significant (see Figure 3a). Furthermore, the alternative model, testing body image concerns as a mediator of the association between internalization and appearance reasons for exercise was also significant, Sobel’s Z = 5.60, p < .001. Appearance motives for losing weight significantly mediated the association between internalization and body image concerns, Sobel’s Z = 9.08, p < .001, although the direct path remained significant (see Figure 3b). Furthermore, the alternative model, testing body image concerns as a mediator of the association between internalization and appearance motives for losing weight, was also significant, Sobel’s Z = 9.63, p < .001.
The present study examined individual differences in reasons for exercise and in motivation for losing weight, and expands on past research in a number of ways. First, with respect to reasons for exercise, our findings are consistent with previous research (e.g., Strelan & Hargreaves, 2005) showing that health-related reasons for exercise were the highest rated, followed by appearance-related reasons, and then mood/enjoyment reasons receiving the lowest ratings. Also consistent with previous research, women were more motivated to exercise for appearance reasons than were men. Although past research has found gender differences in reasons for exercise, the present study is the first to also examine differences as a function of dietary restraint. Restrained eaters were more motivated to exercise for appearance reasons than were unrestrained eaters. Importantly, there was no gender- by- restrained interaction indicating that both female and male restrained eaters showed an increased motivation to exercise for appearance reasons. This finding fits with a growing body of literature indicating that appearance concerns are increasingly common among men (e.g., REF).