European Bulletin of Adapted Physical Activity Volume 2, Issue 2 (2003) www.bulletin-apa.com ISSN 1379-0595 Determinants of exercise participation in relationship to severity of clinical depression in adult female psychiatric in-patients Ioannis Morres, Peter Van de Vliet, Jan Knapen, Herman Van Coppenolle Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, Belgium Introduction Review of epidemiological evidence suggests that clinical depression is associated with low activity/fitness. The data available suggest a negative association between regular physical activity and depressive and anxiety disorders, and that those who maintain active are less likely to develop depression (Mutrie, 2000). It is suggested that inactivity precedes depression. Acknowledging the antidepressant effect of exercise (e.g. Lawlor & Hopker, 2001), it can be assumed that existing psychological models on exercise participation and adherence might be applicable to this population. Examples of such models are the health belief model, theory of reasoned action, and the theory of planned behaviour (see Biddle and Mutrie, 2001 for an extensive review). Data on the conditions to be fulfilled for exercise participation (so-called 'determinants' of physical activity) are sparse (Biddle & Mutrie, 2001). Besides initial activity rates it seems reasonable to propose that the models outlined also take into account social skills and socio-economic status. These include, among others, the individual's beliefs regarding the effectiveness of taking part in exercise and perceived barriers representing beliefs regarding potentially negative aspects of adopting exercise strategies (Sonstroem, 1988). Within the scope of the present study, such barriers and beliefs towards exercise are discussed in relation to initial affect measures (i.c. depression) in clinically depressed female in-patients. Since self-presentation concerns may be a major source of motivation for participating in physical activity (Biddle, 1997), it is hypothesised that mainly social support skills and perceived beliefs towards exercise are considered to be important determinants of exercise participation. Research shows that recent physical activity levels are related to these self-perceptions (Fox, 1997). Materials and methods The subject group consisted of a total of 38 female adult psychiatric in-patients diagnosed by a psychiatrist as mood-disordered following the DSM-IV criteria (mainly recurrent depressed mood disorders, APA, 1994). Patients completed the Dutch version (Bosscher, Koning, & Van Meurs, 1986) of the Beck Depression Inventory (BDI) with participation reference set at 16 or more, representing at least moderate depression. Determinants of exercise participation were assessed by means of : (1) a translated version of the Social Support Scale for exercise (SSS) (Anderson & Fox, 1999), which includes 8 items