Testing the physical activity self-definition model in the context of the ENCOURAGE trial

Abstract

Physical activity (PA) self-views are related to PA (Strachan & Whaley, 2013); little is known about how PA self-views develop. The PA self-definition model (PASD) outlines correlates of PASD. In this model, PASD is associated with PA commitment and ability. PA commitment is influenced by perceptions of PA wanting which is influenced by PA enjoyment. Perceptions of PA trying impact perceived commitment and perceived ability. Cross-sectional support for this model exists among active samples. Presently, the model is assessed among a previously inactive sample to determine if changes in model variables over the course of a PA program lead to change in PASD. Participants were 64 insufficiently-active people between the ages of 30 and 65 who completed ENCOURAGE (a quasi-experimental PA demonstration project).  Upon physician recommendation, participants participated in 5 kinesiologist visits over 16 weeks to increase PA.  At both baseline and intervention-end (16 weeks), participants completed measures of  PA enjoyment, perceived wanting, trying, commitment and ability related to PA and PASD. Path analysis revealed that the PASD model was not supported (chi square = 47.79; RMSEA = .183; p < .001; CFI = .784). The addition of paths from perceived wanting to PASD and from perceived ability to commitment led to a model with acceptable fit (chi square = 16.20; p < .013; RMSEA = .11; CFI = .95). The additional paths may be explained by the previously inactive status of the present sample. PASD model variables should be directly targeted in future interventions to maximize increases in PASD.