Investigating the Effectiveness of Physical Activity Interventions for Older Adults

Regular physical activity can help prevent chronic conditions and it is positively linked to health-related quality of life (United States Department of Health and Human Services [USDHHS], 2000). Unfortunately, many older adults do not engage in leisure time activity (USDHHS, 2000); making it important to design and test physical activity interventions for this population. The purpose of this dissertation was to review the external validity of theory-based physical activity interventions and to examine the efficacy of a mail-based physical activity intervention. The review included 54 theory-based interventions and overall the studies focused on internal rather than external validity. The hypotheses of the experimental study were that the psychological mediators and physical activity participation would significantly increase among the treatment group as compared to the control group, and that the changes in the mediators would be related to the changes in activity levels. The intervention included 4 weekly stage-matched packages targeting population specific physical activity beliefs (Antikainen et al., 2009) and weekly phone calls to reassess stages of change. Physical activity participation, stages of change, and theory of planned behavior constructs were assessed at baseline and follow-up. Differences in activity levels and theory-based constructs were assessed with repeated measures mixed analysis of variance. Stage of change progression was examined with chi-square analysis. Measured variable path analysis was used to determine associations between the theory constructs, stages of change, and physical activity participation. The participants were 55 older adults, ages 54 to 96 years. Most of the participants were female, Black, and reported low levels of education and income. The treatment group reported statistically significantly greater physical activity after the intervention than the control group that reported lower levels of activity at follow-up. Although not statistically significant, there was a trend in SOC progression after the intervention in the treatment group. Finally, the integrated model was found to have a good fit at follow-up and perceived behavioral control emerged as a significant predictor of physical activity. This research provides important information for the design of physical activity interventions based upon the integrated framework for translation to community-based organizations