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As outlined in the introduction, there are a number of inconsistencies within the literature in terms of the terminology and definitions used to describe exercise within the eating disorders. As a consequence, there are a large number of measures that have been proposed and used depending on the theoretical perspective that is adopted with regards to the role of exercise in the eating disorders. The following section provides a description and a critique of the measures available, and a justification for the measure chosen for use within this thesis. This research explores the multidimensional model of exercise within the eating disorders (Meyer et al., 2011). The model incorporates cognitive-behavioural motivations for exercise, such as compulsivity and affect regulation, in addition to weight and shape motivations (Meyer et al., 2011). As such, the

Compulsive Exercise Test was deemed the most appropriate choice of exercise measure for use within this thesis.

The Compulsive Exercise Test (Taranis, Touyz & Meyer, 2011; Appendix I)

The Compulsive Exercise Test is a new 24-item self-report measure based on the multidimensional model of compulsive exercise, designed for use in the eating disorders domain. It has five subscales: (a) Avoidance and Rule Driven Behaviour, (b) Weight Control Exercise, (c) Mood Improvement (d) Lack of Exercise Enjoyment, and (e) Exercise Rigidity. An example item is “If I cannot exercise, I feel anxious.” Responses are scored on a 6-point scale anchored from 0 (never true) to 5 (always true); intermediate response points are 1 (rarely true), 2 (sometimes true), 3 (often true), and 4 (usually true). Higher scores indicate a greater degree of compulsive exercise. The global score is the sum of the means of the five individual subscales. The Compulsive Exercise Test has shown good internal consistency for the individual subscales (α ≥ 0.71) and global score (α ≥ 0.85) among both adult and adolescent samples (Goodwin et al., 2011; Taranis et al., 2011). However, the validity of the multidimensional model of exercise within the eating disorders has yet to be verified with an athlete population. One focus of this thesis is to assess the suitability of the Compulsive Exercise Test for use with athlete samples.

Other theories of exercise within the eating disorders have conceptualised exercise as “addictive”, focusing primarily on the notion of withdrawal when exercise is prevented and the volume of exercise completed (Davis; 1997; Davis & Claridge, 1998; Davies & Woodside, 2002; Dishman, 1985). This has resulted in a variety of measures that have attempted to capture exercise as an addictive behaviour, including the Obligatory Exercise Questionnaire (Pasman & Thompson, 1988); the Commitment to Exercise Scale (Davis, Brewer & Ratusny, 1993); the Exercise Dependence Scale (Hausenblas & Downs, 2002) and the Exercise Orientation Questionnaire (Yates, Edman, Crago, Crowell & Zimmerman, 1999).

Obligatory Exercise Questionnaire (OEQ; Pasman & Thompson, 1988)

The Obligatory Exercise Questionnaire (OEQ) is a 21-item questionnaire based on Blumenthal and colleagues’ Obligatory Running Questionnaire (Blumenthal, O’Toole & Chang, 1984). The OEQ is scored on a 4-point Likert scale from 1 (never) to 4 (always), with higher scores indicative of greater obligatory exercise. An example item is as follows: “When I miss a scheduled exercise schedule I may feel tense, irritable or depressed”. The measure has been shown to have good internal reliability (Pasman & Thompson, 1988; Coen & Ogles, 1993), and has been linked with eating psychopathology among athletes (e.g., Gapin & Petruzzello, 2011) and non-athletes (Thome & Espelage, 2007). However, it is now widely accepted that the OEQ only evaluates certain aspects of exercise dependence, and thus fails to provide an overall assessment of the construct (Hausenblas & Symon Downs, 2002).

Commitment to Exercise Scale (CES; Davis, Brewer & Ratusny, 1993)

The Commitment to Exercise Scale (CES) is a short measure, made up of just 8 items, and is therefore quick and easy to administer. It is designed to assess a pathological commitment to exercise, and has been used frequently within eating disorder research. (Lipsey, Barton, Hulley & Hill, 2006; McLaren, Gauvin & White, 2001; Mond, Hay, Rodgers, Owen & Beumont, 2004b). Higher scores are indicative of more pathological behaviour and beliefs towards exercise. The original measure was scored on a continuum line between two opposing adjectives (Davis et al., 1993). However, this has been recently revised to score on a 4-point Likert scale, and has since demonstrated acceptable internal reliability (Thome & Espelage, 2007). An example item is “Does it upset you, if, for one reason or another, you are unable to exercise?” The CES has been found to correlate with eating psychopathology among athletes (de Sousa Fortes, Neves, Filgueiras, Almeida & Ferreira, 2013). A drawback of the measure is the lack of defined cut-off score to indicate pathological exercising among participants. In addition, the measure does not take into account the role of exercise in affect regulation.

Exercise Dependence Scale (EDS; Hausenblas & Symons-Downs, 2002b)

The Exercise Dependence Scale (EDS) was developed in response to a perceived lack of ‘complete’ measure of exercise dependence that could assess all aspects of the exercise dependence construct among exercisers (Hausenblas & Symons-Downs, 2002b). In addition, it aimed to discriminate between those at risk, symptomatic and asymptomatic for exercise dependence. Exercise dependence was operationalised according to the DSM-IV criteria for substance dependence (APA, 1994). The original measure had 28 items, which was reduced to 21 in a later revision (Symons-Downs, Hausenblas & Nigg, 2004). It is measured on a 6-point Likert scale from 1 (never) to 6 (always), with higher scores indicative of greater exercise dependence. An example item is as follows: “I organise my life around exercise”. The measure has been found to be suitably valid and reliable (Symons-Downs et al., 2004) and is closely linked to levels of eating psychopathology (Cook & Hausenblas, 2008), but the EDS has yet to be used extensively with athletes.

The Exercise Orientation Questionnaire (EOQ; Yates, Edman, Crago, Crowell & Zimmerman, 1999

The final exercise measure to be considered for use in this thesis was the Exercise Orientation Questionnaire (EOQ; Yates et al., 1999) The EOQ was partly developed in response to a lack of an exercise measure that could identify athletes at risk of an eating disorder (Yates et al., 1999). The measure is made up of 27 items, which are scored on a Likert scale of 1 (strongly disagree) to 5 (strongly agree); e.g. “I try to exercise instead of snacking”. The initial validation

adequate reliability and discriminant validity of the EOQ, (Yates et al., 1999; Yates, Edman, Crago & Crowell, 2001). However, the measure has not been widely adopted in investigations exploring eating psychopathology among athletes.

Summary: Measures of exercise attitudes and behaviours

There are a wide variety of measures within the literature that have been developed to explore the role of exercise both within the context of the eating disorders, and more broadly. This perhaps reflects the different theoretical perspectives and definitions that are ascribed to exercise (Meyer, Taranis & Touyz, 2008). As such, there is an absence of a comprehensive measure of the multidimensional nature of exercise within the eating disorders that has been identified as relevant and appropriate for athletes. The Compulsive Exercise Test (Taranis et al., 2011) takes into account the multidimensional nature of exercise in the eating disorders, with a focus on the cognitive-behavioural motivations for exercise. This is in contrast to the exercise addiction and exercise dependence perspective that has been the focus of the field for some time, despite a lack of supporting evidence (Mond, Myers, Crosby, Hay & Mitchell, 2008; Taranis et al., 2011). As such, the CET was determined as the most appropriate measure with which to assess athlete exercise attitudes; although it was acknowledged that it would first need to be appropriately validated with an athlete sample. As such, study 1 explored the validity of the CET for use within an athlete population. Subsequently, this thesis aimed to explore the links between exercise attitudes and eating psychopathology in the athlete population, and to explore whether such a measure might be suitable for identifying those athletes with elevated levels of eating psychopathology i.e. as a potential screening tool for use within the athlete population. Studies 2 and 3 explore the links between exercise attitudes and eating psychopathology in more depth, and assess the validity of the CET as a potentially suitable screening measure for use within the sporting context.