Excessive exercise played a big role in my eating disorder and, predictably, I am drawn to studies that look at the role excessive exercise plays in eating disorder symptomatology, course and outcome. This topic has captured the interest of many eating disorder researchers, with studies revealing that up to 80% of individuals with anorexia nervosa may exercise excessively (Davis et al., 1997), though others suggest more modest statistics, around 39% (Shroff et al., 2006; Tetyana wrote a post about this article here).
Scholars have also noted the potentially obsessive and compulsive nature of exercise among some individuals with eating disorders and have made the natural transition toward examining whether links exist between excessive exercise and obsessive-compulsive disorder (OCD) and/or obsessive-compulsive personality disorder (OCPD) traits (If you are confused about the difference between OCD and OCPD, click here). Young, Rhode, Touyz & Hay (2013) conducted a rigorous systematic review to synthesize and draw conclusions from the results of such studies.
The authors aimed to clarify the links between both OCPD traits and OCD and excessive exercise among individuals with AN. They performed literature searches and identified 10 studies that met their stringent criteria for content and quality. Among the studies chosen, participants were engaged in various forms of treatment (both inpatient and outpatient) for AN in the US, Canada, Germany, Spain, Slovenia, and the UK. Six studies used a cross-sectional design, two were retrospective, one was prospective and one was quasi-experimental.
Studies used a number of different self-report questionnaires and clinical interviews to obtain their results. Of course, trying to compare studies using various instruments and different definitions of what counts for excessive exercise, for example, can be difficult and can be bit of a methodological minefield. However, while the authors acknowledged the potential pitfalls of their method, they still came to some interesting conclusions based on the studies they analyzed.
WHAT COUNTS AS EXCESSIVE EXERCISE?
The first hurdle faced when comparing a number of studies looking at the relationship between OCDP, OCD, and excessive exercise is determining what qualifies as “excessive.” Different scales measuring this construct use different definitions, usually relying on a combination of:
- The frequency and duration of the exercise
- The conditions surrounding the exercise (e.g. “at inappropriate times,” in lieu of other activities, or while ill or injured)
- Mood state/feelings surrounding exercise (e.g. guilt if one does not exercise, lack of enjoyment of exercise)
OCDP vs. OCD
There are a number of differences between OCPD traits and OCD that warrant mentioning in order to interpret this article’s findings. OCPD traits were measured using clinical interviews or trait inventories. These instruments identify individuals with an “obsessional personality type,” which incorporates traits such as perfectionism, drive for order and symmetry, as well as excessive doubt. OCD, measured in these studies using self-report questionnaires, is assessed based on symptoms (e.g. washing, obsessing, ordering, etc.) and the distress associated with these symptoms.
This paper included studies that looked at OCPD, OCD, or both, in relation to excessive exercise. They found that the relationship between OCD and excessive exercise does not appear to be the same as between OCPD and excessive exercise.
THE RELATIONSHIP BETWEEN EXCESSIVE EXERCISE AND OCD
Several of the studies found links between these two constructs:
- Regardless of dietary status, patients who engaged in excessive exercise had significantly higher numbers of obsessive-compulsive symptoms (Davis & Kaptein, 2006)
- Stronger feelings of obligation and pathological attitudes were related to exercise among individuals with AN presenting with excessive exercise (Davis et al., 1995)
- Positive correlation between activity level and “obsessive-compulsiveness” (Davis et al., 1995)
- Lnks between obsessive beliefs, behaviours, exercise behaviour and eating disorder psychopathology (Naylor et al., 2011)
- Positive relationship between excessive exercise and rituals/preoccupations and obsessions/compulsions (Shroff et al., 2006)
Importantly, some studies found no differences in OCD between individuals who exercised excessively and those who didn’t (Anderluh et al., 2009; Holtkamp et al., 2004). Others actually found negative correlations, suggesting that those with OCD may be less inclined to exercise excessively (Penas-Lledo et al., 2002).
From these mixed results, the relationship between excessive exercise and OCD remains unclear. The authors attribute these different findings to differences in measurement; those studies finding negative correlations used a more comprehensive model, adding in more potential confounding variables into the mix in an attempt to clarify relationships.
THE RELATIONSHIP BETWEEN EXCESSIVE EXERCISE AND OCPD
The link between OCPD and excessive exercise appears to be stronger. Several of the studies in this review found that individuals who presented with excessive exercise had a higher lifetime prevalence of OCPD traits, particularly self-oriented perfectionism (Davis et al., 1995).
Being more rule-bound and cautious as a child, though not necessarily during the eating disorder, was also related to excessive exercise (Anderluh et al., 2009).
The relationship between OCD, OCPD traits, and excessive exercise in individuals with AN is complex. One model seeking to explain the relationship between OCPD traits and excessive exercise in particular suggests that excessive exercise combined with obsessive-compulsive traits and reduced dietary intake may contribute to the development and maintenance of anorexia nervosa (Davis et al., 1995).
According to this model, excessive exercise and reduced dietary intake would increase obsessive-compulsiveness, which could in turn lead to a higher level of exercise and further decreases in dietary intake with the increasing obsessions.
COMPLEXITY AND INDIVIDUALITY
The reasons why individuals exercise excessively are as varied as individuals themselves. Obsessionality seems to be one potential driving force, as studies in this review indicate that exercise may be used in an attempt to reduce anxiety and/or to numb obsessional thoughts. This finding in particular spoke to me because exercise, for me, was certainly a way of stopping thoughts entirely, including various anxieties and obsessions.
This review looked only at OCD/OCPD traits/excessive exercise links among individuals with AN. I would be curious to see what results would be found when looking at these links among individuals with BN and/or EDNOS.
Certainly, the lack of clarity in defining constructs, especially “excessive exercise” limits the extent to which we can be sure of the results. As interesting as systematic reviews can be for giving us a great deal of information from a number of different studies, there is always the risk of comparing apples to oranges, particularly when there are large differences in the way the studies were conducted.
Nonetheless, this review is a useful start to clarifying the links between OCD and OCPD traits and excessive exercise among individuals with AN, and may spark further interest in conducting more studies in this vein… such as, perhaps, a qualitative investigation asking patients about their experiences with (and understanding of) obsessive-compulsive traits and excessive exercise?