Increasing physical activity intentions and physical activity behaviour using a media-based intervention informed by protection motivation theory in women at an increased risk of developing breast cancer

Abstract

Purpose: Physical activity (PA) has been shown to decrease breast cancer risk. Using protection motivation theory (PMT), this study explored whether a media-based intervention that presented factual breast cancer and PA information could motivate atrisk women to increase their PA levels. Method: Inactive women (N= 60) were randomly assigned to one of three groups: (1) PMT intervention, (2) attention control, or (3) noncontact control group. The PMT intervention watched a DVD containing information on PA and breast cancer risk based on PMT constructs (i.e., perceived severity [PS], perceived vulnerability [PV], response efficacy [RE], and self-efficacy [SE]), while the attention control group watched a DVD that contained general diet and cancer information. PMT constructs and PA intentions were measured pre- and post-DVD, and PA was measured subjectively and objectively pre- and post-DVD and at 4-week followup. Results: Participants in the PMT intervention group showed significant improvements in coping appraisal constructs after watching the DVD (i.e., RE and SE). RE was also found to significantly predict PA intention scores pre-DVD and post-DVD. No significant changes were found for PA behaviour. Conclusions: The PMT-based PA intervention successfully increased participants’ belief that PA decreases breast cancer risk and that they can perform the required amount of PA to decrease their risk. Further research is needed on the threat appraisal component of PMT and on the inclusion of objective measures of PA in intervention research