Physical Activity in Eating Disorders: A Systematic Review

Abstract

Abnormally high levels of physical activity have been documented throughout the literature in patients with eating disorders (ED), especially those diagnosed with anorexia nervosa (AN). Yet no clear definition, conceptualization, or treatment of the problematic use of physical activity (PPA) in ED patients exists. The aim of this review is to propose a new classification of PPA, report the prevalence, triggers, predictors, maintainers and other related factors of PPA in ED patients, in addition to proposing a comprehensive model of the development of PPA in AN. A total of 47 articles, retrieved from Medline and Web of Science, met the inclusion criteria and were included in the analysis. As a result, the new approach of PPA was divided into two groups (group 1 and group 2) according to the dimension (quantitative vs qualitative approach) of physical activity that was evaluated. The prevalence of PPA in ED was reported in 20 out of 47 studies, the comparison of PPA between ED versus controls in 21 articles, and the links between PPA and psychological factors in ED in 26 articles, including depression (16/26), anxiety (13/26), obsessive–compulsiveness (9/26), self-esteem (4/26), addictiveness (1/26), regulation and verbal expression of emotions (1/26) and anhedonia (1/26). The links between PPA and ED symptomatology, PPA and weight, body mass index (BMI) and body composition in ED, PPA and age, onset, illness duration and lifetime activity status in ED, PPA and ED treatment outcome were reported in 18, 15, 7, 5 articles, respectively. All of the factors have been systematically clustered into group 1 and group 2. Results focused more on AN rather than BN due to the limited studies on the latter. Additionally, a model for the development of PPA in AN patients was proposed, encompassing five periods evolving into three clinical stages. Thus, two very opposite components of PPA in AN were suggested: voluntarily PPA increased in AN was viewed as a conscious strategy to maximize weight loss, while involuntarily PPA increased proportionally with weight-loss, indicating that exercise might be under the control of a subconscious biological drive and involuntary cognition.

Physical activity behaviors and attitudes among women with an eating disorder: a qualitative study

“…They used terms such as "compulsive exercise," 2 "unhealthy exercise," "over-exercise," "overactivity," and "exercise dependence" when describing their PA behavior at the onset and/or height of their ED. This aligns with reports that suggest the prevalence of dysfunctional PA behavior varies between 30 and 80% [35,36], and that it is higher among adults with anorexia nervosa than in healthy controls [see [58] for a review]. Collectively, these findings highlight the need to address women's dysfunctional PA behaviors and attitudes to help them establish healthy PA levels and cope effectively with periods of inactivity.…”

High levels of physical activity in female adolescents with anorexia nervosa: medical and psychopathological correlates

“…From a psychopathological perspective, our results showed no significant differences between the two groups with reference to AN symptomatology. These data were consistent with other studies [12], that examined general eating disorder pathology with either levels of physical activity [18,26], actimetry [15] or locomotor activity [54], but in contrast to those works that underlined the presence of greater weight preoccupation, body dissatisfaction and drive for thinness in the high-PA group than in controls [55,56]. Furthermore, we did not find any significant differences when assessing the presence of symptoms such as compulsivity or anxiety traits, measured by SCL-90, in the two groups.…”

“…Overexercising negatively affects the course of AN, given the demonstrated association between PA and longer length of hospital stay [8], poor treatment outcome [9], interferences with refeeding strategies and body weight stabilisation [10] and increased risk of relapse and chronicity [11,12]. Exercise is sometimes voluntarily increased as a conscious strategy to optimise weight loss and often becomes a coping strategy to compensate, suppress, and/ or alleviate both negative affective states, anxiety [13,14], depression [13] stress and ED symptoms [15], including weight preoccupation [12,16]. As the ED progresses, involuntary PA could appear, with automation of the behaviour as a compulsive component not under voluntary cognitive control (maintaining muscles contracted without even thinking about it, running instead of walking and/or standing up when one normally should be sitting down), adding to voluntary exercise.…”

“…Previous research has focused on the neurobiological regulation of increased physical activity (PA) during severe energy restriction [20]. Research investigating the linkage between PA levels and age at AN onset showed that the levels of PA tend to increase with age [3,12,21]. Studies assessing the potential linkage between PA levels and weight, body mass index (BMI) or body composition provided conflicting results [12], with half of them ruling out any correlations, and the other half showing a significant association between PA and body weight [22,23], BMI [23][24][25][26], percentage of body fat [23,24] and resumption of menses [27].…”

“…Research investigating the linkage between PA levels and age at AN onset showed that the levels of PA tend to increase with age [3,12,21]. Studies assessing the potential linkage between PA levels and weight, body mass index (BMI) or body composition provided conflicting results [12], with half of them ruling out any correlations, and the other half showing a significant association between PA and body weight [22,23], BMI [23][24][25][26], percentage of body fat [23,24] and resumption of menses [27]. Several studies also suggest the association between high PA levels and eating disorder-specific psychological factors, such as eating disorder severity [5,28], depression, obsessive-compulsiveness and symptoms of anxiety disorders [8,15,28,29].…”