Efficacy of an individualized, motivationally-tailored physical activity intervention

This study compared the efficiency of two low-cost interventions for physic al activity adoption. Sedentary (N = 194) adults recruited through newspape r advertisements were randomised to receive either a motivationally-matched , individually-tailored intervention (IT) or a standard self-help intervent ion (ST). Assessments and interventions were delivered by repeated mailings at baseline, one, two, three, and six months. Participants were assessed r egarding current physical activity behavior, motivational readiness to adop t regular physical activity, and psychological constructs associated with p hysical activity participation (e.g. self-efficacy, decisional balance). Re peated measures analyses of variance (ANOVAs) revealed significant increase s in physical activity participation between baseline and six months for bo th groups with a significantly greater increase among IT participants. The IT group outperformed the ST group on all primary outcome measures: (a) min utes of physical activity per week, (b) reaching Centers for Disease Contro l and American College of Sports Medicine (CDC/ACSM) recommended minimum ph ysical activity criteria, and (c) achieving the Action stage of motivationa l readiness for physical activity adoption. Both groups showed significant improvement between baseline and six months on the psychological constructs associated with physical activity adoption (e.g. self-efficacy), with no s ignificant differences observed between the treatment groups. Utilizing com puter expert systems and self-help manuals to provide individually-tailored , motivationally-matched interventions appears to be an effective, low-cost approach for enhancing physical activity participation in the community.