Adding planning strategies to an experiential and conceptual knowledge-based intervention: Does it help to reduce sedentary time?

Objective

The study compared the effects of an “active” control condition addressing conceptual and experiential knowledge about sedentary behavior, with an intervention condition combining conceptual and experiential knowledge together with action planning, coping planning, and behavioral substitution. We targeted a decrease in sedentary time as the primary outcome.

Methods

A preregistered trial (#NCT04131270) was carried out with 603 participants aged 11–86 years (M = 33.57; 65.2% women), randomly assigned to the “planning + knowledge” condition or the “knowledge” condition. Sedentary time was assessed with ActiGraph wGT3X-BT accelerometers at baseline, 1-week, and 36-week follow-ups. Conceptual knowledge strategies involved information about health consequences and instructions on how to perform behaviors while experiential knowledge was enhanced by participants taking/discussing photographs of their home environment that has been triggering sedentary behavior. Action/coping plans referred to ways to substitute sedentary behavior with bouts of physical activity behaviors. Mixed models were fit.

Results

No significant Time × Condition interaction was found. In the total sample, sedentary time estimated to be around 502.34 min/day at baseline, showed a significant linear decline over time (p = .002), by approximately −1.22 min per each month elapsing since baseline (−9.76 min/day across 8 months).

Conclusions

The findings suggest that applying behavior change techniques targeting both conceptual and experiential knowledge about antecedents, circumstances, and consequences of sedentary behavior may result in a small reduction of sedentary time. Adding action plans, coping planning, and behavioral substitution did not improve the effectiveness of the intervention.