The effects of yoga on psychosocial variables and exercise adherence: a randomized, controlled pilot study.

BACKGROUND Physical inactivity is a serious issue for the American public. Because of conditions that result from inactivity, individuals incur close to $1 trillion USD in health-care costs, and approximately 250 000 premature deaths occur per year. Researchers have linked engaging in yoga to improved overall fitness, including improved muscular strength, muscular endurance, flexibility, and balance. Researchers have not yet investigated the impact of yoga on exercise adherence. OBJECTIVE The research team assessed the effects of 10 weeks of yoga classes held twice a week on exercise adherence in previously sedentary adults. DESIGN The research team designed a randomized controlled pilot trial. The team collected data from the intervention (yoga) and control groups at baseline, midpoint, and posttest (posttest 1) and also collected data pertaining to exercise adherence for the yoga group at 5 weeks posttest (posttest 2). SETTING The pilot took place in a yoga studio in central New Jersey in the United States. The pretesting occurred at the yoga studio for all participants. Midpoint testing and posttesting occurred at the studio for the yoga group and by mail for the control group. PARTICIPANTS Participants were 27 adults (mean age 51 y) who had been physically inactive for a period of at least 6 months prior to the study. Interventions The intervention group (yoga group) received hour-long hatha yoga classes that met twice a week for 10 weeks. The control group did not participate in classes during the research study; however, they were offered complimentary post research classes. Outcome Measures The study's primary outcome measure was exercise adherence as measured by the 7-day Physical Activity Recall. The secondary measures included (1) exercise self-efficacy as measured by the Multidimensional Self-Efficacy for Exercise Scale, (2) general well-being as measured by the General Well-Being Schedule, (3) exercise-group cohesion as measured by the Group Environment Questionnaire (GEQ), (4) acute feeling response as measured by the Exercise-induced Feeling Inventory (EFI), and (5) two open-ended questions coded for emerging themes and subcategories. RESULTS The analysis revealed that the yoga group's mean hours of physical activity at 10 weeks reflected a significant increase in exercise adherence from baseline (P < .012) and a significant difference from the control group (P < .004). At 5 weeks post-intervention, no significant change had occurred in the yoga group's exercise adherence (P = .906). Exercise self-efficacy changed significantly from baseline to midpoint (P < .029). The general wellbeing data demonstrated a significant interaction effect (P < .001), resulting from an increase in general well-being in the intervention group and a decrease in general well-being in the control group. In addition, the yoga group's cohesion score was consistent with the norms on two constructs of the GEQ: Attraction to Group Task and Group Integration Task. The EFI revealed that the yoga participants "felt strongly" that their experiences in yoga were peaceful, happy, upbeat, and enthusiastic and that they felt revived following the yoga classes. Qualitative analysis of data revealed self-reported improvements in exercise behaviors, stress management, and eating habits. CONCLUSIONS Ten weeks of yoga classes twice a week significantly increased previously inactive participants' adherence to physical activity. Additionally, the findings suggest that a mind-body exercise program may be an effective intervention in the fight against physical inactivity.