Abstract
Minimizing the exercise intention-behaviour gap remains an ongoing research pursuit. Daily temptations and choices have been shown to weaken self-regulation (Muraven & Baumeister, 2000). ‘Morning people’ may be more apt to higher levels of self-control and physical activity than ‘evening people’ (Digdon & Howell, 2008; Urbán et al., 2011). We hypothesized that intentions to exercise in the afternoon/evening would be less likely to be followed through than intentions to exercise in the morning. Study 1 (115 adults working full time) assessed exercise intentions and behaviour over the past week. Study 2 (191 students) prospectively assessed intentions to exercise over the next week, and one week later assessed actual exercise behaviour from the past week. In both studies, there was no inconsistency between average exercise intentions and average exercise bouts in the morning (t=0.73, p=0.469; t=1.46, p=0.147), however there was significant incongruence between evening intentions and behaviour (t=2.33, p=0.022; t=5.06, p<0.001). Participants who made at least one intention to exercise in the morning had a significantly (t= 3.74, p<0.001; t= 4.97, p<0.001) greater number of total exercise bouts (4.54 bouts ±2.19; 7.85 bouts ±4.73) than those who intended to exercise at later times (2.87 bouts ±1.94; 4.61 bouts ±3.08). Lastly, the greatest number of intentions that were not carried through occurred for intentions made between 5-8PM in both studies, despite unique patterns of exercise intentions. These results support the notion that self-regulation is depleted throughout the day, and lends itself to practical advice as to when to schedule exercise bouts.
