Text Messages Promoting Mental Imagery Increase Self-Reported Physical Activity in Older Adults: A Randomized Controlled Study.

Objective: This study tested whether text messages prompting adults 50 years of age and older to perform mental imagery would increase aerobic physical activity (APA) duration using a randomized parallel trial design.

Method: Participants were assigned to an Imagery 1, Imagery 2, or placebo group. For 4 weeks, each group was exposed to two conditions (morning text message vs. no morning text message). In the morning message condition, the imagery groups received a text message with the instruction to mentally imagine performing an APA, and the placebo group received a placebo message. All participants received an evening text message of "Did you do your cardio today? If yes, what did you do?" for 3 days per week.

Results: Participants of the imagery groups reported significantly more weekly minutes of APA in the morning text message condition compared with the no morning message condition.

Conclusion: Electronic messages were effective at increasing minutes of APA.