Factorial Trial Testing Guided Thinking Tasks to Optimize a Physical Activity Intervention

Study Overview
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Brief Summary
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The objective of this study is to optimize a novel, audio-recorded physical activity intervention that is scalable. Using principles of the Multiphase Optimization Strategy (MOST) framework, a full factorial study will test the unique and combined effects of different intervention components to identify which combination of components is optimal for increasing physical activity and mechanisms by which the components are or are not effective. This information will inform decisions about an optimal intervention package that is effective, efficient, and minimizes participant burden.

Detailed Description
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Eligible participants who provide informed consent will be enrolled in a 6-week study. At the baseline session, participants will be randomized to listen to a brief audio-recording of different guided thinking tasks. The audio-recordings are based on combinations of four different intervention components that will be tested in a 2 (positive affect imagery vs. neutral) x 2 (episodic future thinking vs. recent thinking) x 2 (action planning: yes, no) x 2 (dose: high vs. low) factorial trial. Participants will also complete a 30-minute brisk walking session on a treadmill. Participants will return for weekly visits in which they again listen to their assigned audio-recording and complete a 30-minute brisk walking session.

Official Title
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Factorial Trial to Test Unique and Combined Effects of Guided Thinking Tasks to Optimize a Physical Activity Intervention Among Underactive Adults

Conditions
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Physical Inactivity

Intervention / Treatment
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* Behavioral: Episodic future thinking
* Behavioral: Positive affect imagery
* Behavioral: Action planning
* Behavioral: High dose
* Behavioral: Recent thinking
* Behavioral: Neutral imagery
* Behavioral: Low dose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults ages 18-64 Not currently meeting physical activity guidelines (<150 minutes/week of self-reported moderate-to-vigorous physical activity) Capable of providing informed consent Access to a smartphone with active data plan Willing to attend all study visits and comply with the protocol Conversant in English Exclusion Criteria: BMI > 40 orthopedic problems that would limit physical activity self-reported coronary artery disease, stroke, COPD, chronic bronchitis, emphysema, diabetes

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Condition 1<br>1) Episodic future thinking; 2) Positive affect imagery; 3) Action planning; 4) High intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>|
| Experimental: Condition 2<br>1) Episodic future thinking; 2) Positive affect imagery; 3) Action planning; 4) Low intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 3<br>1) Episodic future thinking; 2) Positive affect imagery; 3) High intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>|
| Experimental: Condition 4<br>1) Episodic future thinking; 2) Positive affect imagery; 3) Low intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 5<br>1) Recent thinking; 2) Positive affect imagery; 3) Action planning; 4) High intervention dose | Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>|
| Experimental: Condition 6<br>1) Recent thinking; 2) Positive affect imagery; 3) Action planning; 4) Low intervention dose | Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 7<br>1) Recent thinking; 2) Positive affect imagery; 3) High intervention dose | Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>|
| Experimental: Condition 8<br>1) Recent thinking; 2) Positive affect imagery; 3) Low intervention dose | Behavioral: Positive affect imagery<br>* Participants will listen to a guided thinking task directing them to think about positive feelings and associations about physical activity in specific, personal, and positive detail.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 9<br>1) Episodic future thinking; 2) Neutral imagery; 3) Action planning; 4) High intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>|
| Experimental: Condition 10<br>1) Episodic future thinking; 2) Neutral imagery; 3) Action planning; 4) Low intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 11<br>1) Episodic future thinking; 2) Neutral imagery; 3) High intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>|
| Experimental: Condition 12<br>1) Episodic future thinking; 2) Neutral imagery; 3) Low intervention dose | Behavioral: Episodic future thinking<br>* Participants will listen to a guided thinking task directing them to think about themselves at a future, positive event and to imagine the event in vivid and specific detail.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 13<br>1) Recent thinking; 2) Neutral imagery; 3) Action planning; 4) High intervention dose | Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>|
| Experimental: Condition 14<br>1) Recent thinking; 2) Neutral imagery; 3) Action planning; 4) Low intervention dose | Behavioral: Action planning<br>* Participants will listen to a guided thinking task directing them to think about the remainder of their week and when, where, and how they plan to attain their remaining activity for the week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|
| Experimental: Condition 15<br>1) Recent thinking; 2) Neutral imagery; 3) High intervention dose | Behavioral: High dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 5 times/week.<br>Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>|
| Experimental: Condition 16<br>1) Recent thinking; 2) Neutral imagery; 3) Low intervention dose | Behavioral: Recent thinking<br>* Participants will listen to a guided thinking task directing them to think about a regular habit or activity they completed in the past week and to imagine that activity in specific and vivid detail.<br>Behavioral: Neutral imagery<br>* Participants will listen to a guided thinking task directing them to imagine physical sensations (i.e., movements, muscles used) of a routine, daily activity (non-physical activity).<br>Behavioral: Low dose<br>* Participants will listen to the audio-recording with the guided thinking tasks 1 time/week.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Weekly Physical Activity Minutes Across 6 Weeks (accelerometer-assessed) | Amount of weekly moderate-to-vigorous (MVPA) minutes (i.e., minutes of MPVA weighted by intensity) will be determined from accelerometers (ActiGraph wGT3X-BT) worn for one-week periods for six consecutive weeks. | Assessed weekly at Weeks 1-6 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Weekly Physical Activity Minutes Across 6 Weeks (self-reported) | Amount of weekly self-reported MVPA (i.e., minutes of MPVA weighted by intensity) will be determined using the 7-day Physical Activity Recall (PAR) interview. | Assessed weekly at baseline and at Weeks 1-6 |