This two-arm, parallel group, randomized clinical trial will test different types of text messages on daily steps and targeted mechanisms of adherence to physical activity in middle-aged and older adults. All participants will receive baseline education, a wearable Fitbit activity tracker, and up to 4 daily motivational text messages to move more and/or sit less in a 3-month intervention. Intervention will be 3 months with assessments of physical activity, targeted mechanisms of adherence, and cognitive function at baseline, 3-months, and 6-months (3 months post intervention).
This study is a formative step in designing potent and scalable digital health interventions that promote physical activity behavior change and adherence, and cognitive function. Such advancements are needed to determine the link between physical activity and risk of Alzheimer’s Disease and related dementias (ADRD).
Aims are to evaluate the effects of text messages on automatic affective evaluations, habit strength (experienced automaticity), exercise identity, working memory capacity, and processing speed on the outcomes.
The primary outcome will be average daily step counts collected by an activPAL activity monitor. Secondary outcomes include automatic affective evaluations from the Single-category Implicit Association Test (SCIAT), habit strength from the Behavioral Automaticity Index from Self-Report Habit Index, exercise identity from the Exercise Identity Scale, processing speed from the Mobile Monitoring of Cognitive Change (M2C2) Symbol Search Task and working memory capacity from the M2C2 Grid Memory Task.
The study will enroll 150 participants. Both female and male participants will be recruited. Participants will be 40 years of age or older, inactive (i.e., less than 90 minutes of moderate-to-vigorous physical activity per week), living in the continental United States, and able to perform moderate physical activity without restrictions.
Enrollment is targeted to begin in January, 2026.