Objective
Excessive exercise is a common feature of eating disorders (ED) and is associated with earlier ED onset, more ED symptoms, and higher persistence of ED behavior. Research indicates that exercise amount alone is not associated with ED. The purpose of this study was to investigate pathological attitudes and behaviors related to exercise (e.g., exercise dependence) as a mediator of the exercise and ED relationship.
Method
Participants were 43 women with an ED who completed measures of ED symptoms, exercise behavior, and exercise dependence. Analyses were conducted using the indirect bootstrapping method for examining mediation.
Results
Exercise dependence mediated the relationship between exercise and ED. This mediation model accounted for 14.34% of the variance in the relationship.
Discussion
Our results extend the literature by offering preliminary evidence of a psychological variable that may be a candidate for future interventions on the exercise and ED relationship. Implications and suggestions for future research are discussed.
Excessive exercise is a common feature of all eating disorder (ED) variants, with prevalence rates ranging from 21% to 55% (Shroff et al., 2006). Exercise is associated with earlier ED onset, more ED symptoms, and higher persistence of ED behavior (Shroff et al., 2006). However, these detrimental associations are observed despite the amount of exercise engaged in by ED individuals often failing to either meet or exceed recommended physical activity guidelines (Garber et al., 2011 and Peñas~Lledó et al., 2002). Therefore, a need exists to identify psychological variables that may explain how exercise contributes to ED development, maintenance, and relapse (Cook & Hausenblas, 2014).
Exercise dependence is a term used to quantify and describe pathological behaviors and attitudes related to exercise (Hausenblas & Symons Downs, 2002) and refers to a phenomenon that has also been described as addictive, compulsive, driven, and/or obligatory exercise (Cook, Hausenblas, & Freimuth, 2014). Recently, exercise dependence has been identified as an important variable in the exercise and ED relationship (Bratland-Sanda et al., 2011). Specifically, obligatory attitudes and behaviors (i.e., exercise dependence symptoms), not time (i.e., amount) spent exercising, are positive predictors of negative eating attitudes, behaviors, and ED symptoms (Adkins & Keel, 2005). Furthermore, exercise dependence, not exercise behavior, has been shown to mediate the relationship between exercise and ED (Cook and Hausenblas, 2008 and Cook et al., 2011). Thus, psychological factors such as exercise dependence but not exercise amount may explain why the exercise and eating disorder relationship exists. Understanding why this relationship exists may help identify those most at-risk for ED, how exercise exacerbates ED outcomes, and have implications in the role of exercise in ED treatment.
Indentifying potential mediators of the exercise and ED relation is important. However, the mediation effect has only been demonstrated in samples of undergraduate students and using proxy measures of ED behavior (e.g., drive for thinness) as the outcome variable (Cook and Hausenblas, 2008 and Cook et al., 2011). Thus, confirmation of exercise dependence's mediating effect is needed in samples of individuals with ED. Therefore, the purpose of our study was to examine the relationships among exercise behavior, exercise dependence, and ED symptoms in a sample of ED individuals. We hypothesized that exercise dependence would mediate the exercise and ED relationship (Cook and Hausenblas, 2008 and Cook et al., 2011).
The relationship between exercise and ED is understudied despite evidence that exercise is associated with several detrimental clinical outcomes (Bratland-Sanda et al., 2011 and Shroff et al., 2006). Therefore, identifying mediators of this relationship may help direct intervention efforts (Kraemer et al., 2001). Our results extend the literature by offering preliminary evidence of a possible psychological variable that may be such a candidate for future interventions (Hausenblas et al., 2008). Moreover, this pilot study suggests that continued examination of exercise dependence's role in ED development, maintenance, and relapse is warranted.
