Effects of aerobic exercise on symptoms of depression in women
The purpose of the experimental study (posttest-only control group) was to determine the effectiveness of aerobic exercise in reducing depression in women. Selye's neurophysiological theory of stress served as the framework for the study. The sample consisted of 62 subclinically depressed women, ages 18-33, who were self-selected using an inclusion criteria and randomly assigned to either experimental or control group. Data were collected using five questionnaires and three physiological measures. The questionnaires were self-administered health history, Psychiatric Epidemiological Research Inventory (PERI), Demographic, Center for Epidemiological Studies--Depression (CES-D) Scale, and Aerobic Exercise Assessment (AEA). The physiological measures were weighing scale, mercury blood pressure apparatus, and treadmill ECG monitoring system. The treatment consisted of 50 minutes aerobic exercises, three times weekly for eight weeks at 80% intensity sustained for 20 to 25 minutes. Analysis of variance (ANOVA) with Scheffe, multivariate analysis of covariance (MANCOVA), and multivariate analysis of variance (MANOVA) were performed to test three null hypotheses. Results indicated statistically significant differences in postmaximum oxygen uptake (VO(,2) max) at .0001 level and in postdiastolic blood pressure (p < .026). A significant difference was also found in depressive symptomatology (p < .005) between experimental and control groups. A significant interaction was found between aerobic exercise, age, religion, and depression (p < .024). The study corrects major methodological flaws found in previous investigations and extends the small body of knowledge on cardiovascular fitness and depression in women. Results have implications for assertively utilizing aerobic activities as interventions that promote self-responsibility in preventing a potentially chronic mental health problem. Results of the study could provide data for defining nursing's independent and collaborative roles in relation to a health promotive activity that is popular among women nationwide. A replication of the study which includes measurements of biochemical changes associated with depression and exercise in women populations with more varied sociological variables is recommended.