Comparison of Affect-based, Self-selected, and Traditional Exercise Prescriptions

Study Overview
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Brief Summary
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This study will evaluate adherence to four types of walking programs. Participants will be randomized to walking programs that included either (1) affect-based exercise intensity, (2) self-selected (or choice-based) exercise intensity, (3) heart-rate based exercise intensity, or (4) heart-rate guided exercise intensity with the emphasis on affective benefits.

Detailed Description
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The purpose of this study is to determine if an affect-based or choice-based exercise prescription is more effective for behavior change than a traditional, moderate-intensity exercise prescription. Prior research suggests that choice-based or self-selected exercise intensity is more pleasant and adhered to than moderate-intensity exercise (Williams et al., 2014). Similarly, affect-based exercise prescriptions (i.e., an exercise prescription where intensity is regulated based on the pleasure-displeasure one feels while exercising) appear to have merit (Baldwin, Kangas, Denman, Smits, Yamada, & Otto, 2016). However, choice-based and affect-based exercise prescriptions have not been compared to each other. Further, it is unknown if it is the intensity regulation that matters (e.g., choose an intensity that feels good or the focus on affect (e.g., focus on feeling good). Third, prior research has not objectively measured physical activity behavior.

Official Title
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Comparison of Affect-based, Self-selected, and Traditional Exercise Prescriptions

Conditions
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Physical Activity

Intervention / Treatment
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* Behavioral: Choice-based Exercise Intensity
* Behavioral: Positive Affect Focus
* Behavioral: Heart rate-based Exercise Intensity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be fluent in English Must be able to walk Exercise less than 90 minutes per week at a moderate-intensity Must be able to attend laboratory visits Must have mobile internet accent and a personal smartphone (iPhone iOS 9+ or Android OS 4.3+) Can safely exercise at an intensity that is at least moderate Exclusion Criteria: People who are recommended to have medical clearance prior to exercising, according to the American College of Sports Medicine's preparticipation screening criteria, will be excluded

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Choice-No Affect<br>These participants self-select (i.e., choose) their exercise intensity with the goal of walking 30-60 minutes on most days of the week. For safety reasons, they are instructed not to exceed 59% of their heart rate reserve. This is choice-based exercise intensity with no focus on positive affect. | Behavioral: Choice-based Exercise Intensity<br>* Participants are instructed to choose whichever intensity they want, rather than regulate their intensity based on heart rate.<br>|
| Experimental: Choice-Affect<br>These participants self-select their exercise intensity with the goal of walking 30-60 minutes on most days of the week. They're instructed to choose the intensity that makes them feel the best. For safety reasons, they are instructed not to exceed 59% of their heart rate reserve. This is choice-based exercise intensity with a focus on positive affect. | Behavioral: Choice-based Exercise Intensity<br>* Participants are instructed to choose whichever intensity they want, rather than regulate their intensity based on heart rate.<br>Behavioral: Positive Affect Focus<br>* Participants are instructed to focus on feeling good while exercising.<br>|
| Experimental: No Choice-Affect<br>These participants regulate their exercise intensity using their heart rate, with the goal of walking 30-60 minutes on most days of the week. The intensity is moderate according to the American College of Sports Medicine (40-59% of their heart rate reserve). Meanwhile, these participants are instructed to focus on the good feelings that come with exercise. this is heart rate-based exercise intensity with a focus on positive affect. | Behavioral: Positive Affect Focus<br>* Participants are instructed to focus on feeling good while exercising.<br>Behavioral: Heart rate-based Exercise Intensity<br>* Participants are instructed to regulate their exercise intensity based on their heart rate.<br>|
| Active Comparator: No Choice-No Affect<br>These participants regulate their exercise intensity using their heart rate, with the goal of walking 30-60 minutes on most days of the week. The intensity is moderate according to the American College of Sports Medicine (40-59% of their heart rate reserve). This is heart rate-based exercise intensity with no focus on positive affect. | Behavioral: Heart rate-based Exercise Intensity<br>* Participants are instructed to regulate their exercise intensity based on their heart rate.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in objectively measured exercise behavior | Minutes per week of objectively measured exercise behavior. | This will be measured throughout the baseline assessment period (2 weeks) and intervention period (4 weeks) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in self-reported exercise behavior | Minutes per week of self-reported exercise behavior that is reported using exercise log. | This will be measured throughout the baseline assessment period (2 weeks) and intervention period (4 weeks) | 
| Change in affective attitudes | Affective attitudes toward exercise | Measured during baseline assessment period and at the end of the intervention | 
| Self-reported intrinsic motivation (questionnaires) | Intrinsic motivation for exercise program | Two weeks into study intervention | 
| Enjoyment | Enjoyment of exercise program. | Measured at the end of the intervention period (4 weeks) | 
| Change in weight | Body weight | Measured at the beginning and end of the study (6 weeks). | 
| Change in resting heart rate | Resting heart rate | Measured at the beginning and end of the study (6 weeks). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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exercise behavior, exercise prescription, affect-based exercise, affect-guided exercise, self-paced exercise, self-selected exercise