The effect of exercise on negative affect has been examined in hundreds of studies. However, the effect of exercise on diagnosed clinical depression has received far less attention. Furthermore, poor methodological techniques predominate and results have been conflicting. A meta-analysis was conducted to investigate the effect of exercise on clinical depression and depression resulting from mental illness. The chosen studies examined the effect of a chronic exercise paradigm (independent variable) on depression (dependent variable). Each study’s variables were coded: design, subjects, exercise, and dependent measure characteristics that could moderate the effect of exercise on depression. Moderator variables were analyzed using analysis of variance (ANOVA). Results from 30 studies showed an overall mean effect of −.72. Therefore, individuals who exercised were −.72 of a standard deviation less depressed than individuals who did not exercise. Moderating variables and implications for the prescription of exercise as an effective treatment for depression are discussed.
Lynette L. Craft and Daniel M. Landers
Lynette L. Craft, T. Michelle Magyar, Betsy J. Becker, and Deborah L. Feltz
The multidimensional approach to the study of anxiety (Martens, Vealey, & Burton, 1990a) considers subcomponents of anxiety, specifically cognitive anxiety, somatic anxiety, and self-confidence. Much of the research based on this theory has utilized the Competitive State Anxiety Inventory (CSAI-2) (Martens, Burton, Vealey, Bump, & Smith, 1990b). Findings have been inconsistent, with some research suggesting that the three subcomponents have separate relationships with performance and other studies failing to find any relationship between the anxiety subcomponents and performance. This meta-analysis examined the effect of state anxiety as measured by the CSAI-2 (i.e., cognitive anxiety, somatic anxiety, and self-confidence) on athletic performance. Studies were coded for characteristics that could potentially moderate the effects of anxiety on performance (i.e., features of design, subjects, sport). Interdependency between the three subscales was examined using multivariate meta-analytic techniques (Becker & Schram, 1994). Relationships among cognitive anxiety, somatic anxiety, self-confidence, and performance appeared weak. Exploratory modeling showed that self-confidence displayed the strongest and most consistent relationship with performance.
Lynette L. Craft, Frank M. Perna, Karen M. Freund, and Larry Culpepper
Exercise effectively reduces symptoms of depression. However, correlates of regular exercise in depressed women are unknown. This study assessed psychosocial determinants of exercise in a sample of women with depressive symptoms.
Sixty-one women completed demographic, depression, and exercise-related questionnaires.
The average Primary Health Ques-tionnaire-9 (PHQ-9) depression score was 12.1 (SD = 5.0), indicating moderate depressive symptoms. In the previous week, the women reported 12.8 metabolic equivalents (METs) of exercise. Low levels of self-efficacy and social support for exercise were also reported. Depressive symptoms were positively associated with barriers to exercise (r = .35, P < .01), and barriers were inversely related to exercise METs (r = –.37, P < .05). Barriers to activity and education level were significant determinants of exercise.
Women with depressive symptoms report minimal exercise involvement, numerous barriers to exercise, and low exercise self-efficacy and social support for exercise.