Feel the Move: A Micro-Randomized Trial of a Text-Based Expectation-Setting Intervention to Increase Physical Activity

Setting Expectations for Enjoyment of Physical Activity

The aim of this research is to evaluate the impacts of an intervention that reminds people of the affective rewards of exercise on physical activity in adults of any activity level

Study Overview

• Status: Completed
• Conditions: Physical Activity
• Intervention / Treatment: Behavioral: Affective Rewards Messages

Detailed Description

The Feel the Move study tests the effects of a lightweight text-message based intervention to increase physical activity and affective attitudes towards exercise. The intervention being investigated is text messages that prime expected affective rewards of exercise, sent in advance of a time window during which participants made plans to exercise. At the start of the study, participants will write sentences about feeling good after exercise (which will be used as part of the intervention) and complete baseline questionnaires about their feelings towards exercise. For the next nine weeks, participants will be asked to plan two exercise sessions a week, and will be given a questionnaire after the time window of their planned exercise sessions to assess how it went. At the onset of each time window for their planned exercise session, participants will be micro-randomized to receive one of the following intervention options: no-message; a text message reminding them to fill out the study questionnaires; or a message about the affective rewards of exercise. The messages about affective rewards will be a mix of sentences participants wrote themselves during the baseline assessment and reflective prompts from the research team. At the nine-week mark, participants will again complete the same questionnaires about their feelings towards exercise that they initially completed at baseline. Throughout the study, participants will share data about their activity, including steps and calories burned, with the research team. These data will be automatically collected by the HIPAA-compliant CareEvolution platform from participants' Apple Watches. After the nine weeks of the study participation, a random sample of study participants will be asked to participate in exit interviews to share more details about their experiences with the intervention.

The primary hypothesis is that participants will burn more calories during their planned exercise periods when they receive messages about the affective rewards of exercise vs. when they do not. Researchers will also conduct secondary analyses examining the effects of the intervention on feelings towards exercise and qualitative data from the interviews.

• Study Type: Interventional
• Enrollment (Actual): 200
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48104
      • University of Michigan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• lives in the US
• 18 years old or older
• desires to increase activity through structured exercise
• has an iPhone that can send/receive text messages and an Apple Watch

Exclusion Criteria:

• medically advised not to exercise

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Affective Rewards Messages; Throughout the study, each week participants will be asked to plan two exercise sessions for the upcoming week, and will be asked to report on how they did with those plans at the end of the day when they planned to exercise. At the very beginning of the time window when they planned to exercise participants will be randomized with 40% probability to receive no message, 20% probability to receive a reminder to fill out the study questionnaire at the end of the day, and 40% probability to receive one of two types of affective rewards messages (active intervention). The two types are: 1) low-reflection messages written by participants at the beginning of the study, about the affective rewards of exercise they have previously experienced; and 2) high-reflection messages that prompt participants to reflect on the affective rewards of exercise and text back a response.

Behavioral: Affective Rewards Messages; Messages about the affective rewards of exercise

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Calories burned in planned exercise session	Calories burned during the four-hour time window when participants planned to exercise	4 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline Expected Post-exercise affect at 9 weeks	Participants will be asked question about their expected post-exercise affect at the beginning and end of the 9 week study	At study completion, 9 weeks after enrollment
Change from Baseline in other affective attitude measures at 9 weeks	Participants will be asked additional questions about their affective attitudes towards and valuations of exercise at the beginning and end of the 9 week study	At study completion, 9 weeks after enrollment

Collaborators and Investigators

• Sponsor: University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): May 31, 2023
• Primary Completion (Actual): November 1, 2023
• Study Completion (Actual): November 30, 2023

Study Registration Dates

• First Submitted: September 21, 2022
• First Submitted That Met QC Criteria: October 14, 2022
• First Posted (Actual): October 17, 2022

Study Record Updates

• Last Update Posted (Actual): June 25, 2024
• Last Update Submitted That Met QC Criteria: June 24, 2024
• Last Verified: June 1, 2024

More Information

Terms related to this study

• Other Study ID Numbers: HUM00190301

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No