Pelham & Campagna (1991) investigated the physiological, psychological and social effects of exercise in out-patients with schizophrenia, using a single-subject design that emphasised interviews and questionnaires. A typical exercise programme consisted of cycling on a ergometer, 4 days per week for 30 minutes per session. Their results indicated a general trend of reduced depression, increased general well-being and improved aerobic fitness. More recently, Faulkner & Sparkes (1999) conducted an ethnographic study that examined the influence of exercise as a therapy for schizophrenia and reported that a 10-week exercise programme of twice-weekly sessions appeared to help reduce participants' perceptions of auditory hallucinations, raise self-esteem and improve sleep patterns and general behaviour.
Craft & Landers (1998) conducted a meta-analytical review of studies that had investigated the effects of exercise on clinical depression and depression resulting from mental illness. A Master's thesis and unpublished Doctoral dissertations and were also included in the analyses. To meet the inclusion criteria for this study, participants had to be suffering from depression as either the primary disorder or as a secondary disorder as the result of mental illness. Results from 30 studies showed an overall mean effect of –0.72, indicating that individuals who exercised were less depressed than their non-active counterparts. This study also concluded that those individuals who were initially more depressed benefited the most from exercise. Several other well-considered reviews (Martinsen, 1993; 1994; Mutrie, 2000; North et al, 1990) have indicated a positive relationship between exercise and clinical depression scores. An example of exercise therapy being used as an adjunctive treatment for depression is described below.
Martinsen et al (1989c) investigated hospitalised patients with various DSM–III (American Psychiatric Association, 1980) anxiety disorders; somatoform disorders; conversion, somatoform pain and somatization disorder; and hypochondriasis. Patients participated in an 8-week specialised aerobic exercise programme (main treatment) and three sessions of group psychotherapy. Anxiety was assessed using the Symptoms Rating Test (Kellner & Sheffield, 1973). No control group was included. During the study, anxiety scores fell significantly in most diagnostic groups. However, 1 year after treatment, those patients who experienced panic disorder with agoraphobia had lost their gains, while those with generalised anxiety disorder and agoraphobia without panic attacks remained well. Patients with social phobia were unchanged at discharge as well as 1 year after treatment. According to Martinsen (1995) these mixed findings may be due to normal variations in the course of different disorders, but they could also highlight that various anxiety disorders respond differently to exercise. Orwin (1974) has also reported positive results with a combination of exercise and exposure to the anxiety-provoking stimuli, although sample size was small.
Several studies have reported a positive association between participation in exercise and enhanced mental health in people who misuse alcohol, with some studies reporting significant changes after relatively short exercise programmes. Gary & Guthrie (1972) found that self-esteem improved along with fitness in a 4-week jogging programme. Other studies using quasi-experimental designs (e.g. Palmer et al, 1988; Preedy & Peters, 1990) reported significant reductions in trait anxiety and depression during exercise. They also found that people with alcohol misuse problems who undertook aerobic exercise were better able to cope with life-stresses after discharge from the alcohol treatment programme. Research has also reported that participation in exercise appears to help reduce levels of alcohol consumption in misusers, although published research in this area remains limited and somewhat contradictory. Using self-report, Sinyor et al (1982) indicated that exercise can be linked to sustained abstinence up to 3 months after discharge from an alcohol treatment programme. Using a multi-site random control study, Donaghy (1997) investigated the relationship between exercise participation and levels of drinking by using serum carbohydrate deficient transferrin (CDT) as a marker of chronic alcohol consumption. No evidence to support a positive relationship between participation in exercise and maintained abstinence or controlled drinking was reported, highlighting a need for further research to clarify this relationship.
