The intention-behaviour gap: An empirical examination of an integrative perspective to explain exercise behaviour

This study tested the Theory of Planned Behavior (TPB) in conjunction with two sets of variables from the Health Action Process Approach (HAPA) and the Subjective Exercise Experience Scale (SEE) to predict exercise behavior. This study included 454 participants who exercised in a fitness center. We collected measures of the TPB (attitudes, subjective norms, perceived behavioral control, and intention), HAPA (planning), and SEE (positive well-being, psychological distress, and fatigue) and assessed exercise behavior at a three-month follow-up. Structural equation modeling found partial support for the TPB model (explaining 10% of the variance in exercise behavior) and adequate fit indices for an adjusted model of the TPB that includes a positive well-being dimension (explaining 11% of the variance in exercise behavior). In sum, the original TPB partially predicts exercise behavior; when considered together with other predictors, limited evidence was found for its utility in explaining exercise behavior.This study was conducted at Psychology Research Centre (UID/PSI/01662/2013), University of Minho, and supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653).