Improving the Experience of Exercise Among Individuals With Internalized Weight Bias Using Acceptance-based Strategies

Study Overview
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Brief Summary
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The goal of this study is to test whether an acceptance based intervention can modify the relationship between heart rate and perceived exertion/negative during physical activity among individuals who have a high degree of internalized weight bias.

Detailed Description
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In this two-phase pilot, we will first test in a controlled setting whether an acceptance-based intervention can modify the relationship between Heart Rate and perceived exertion/negative affect during moderate intensity physical activity among individuals high in internalized weight bias (Phase 1) and then evaluate these mechanisms in real-time during uptake of a two-week physical activity prescription (Phase 2). Using a 2x2 factorial design, we will randomize individuals with Body Mass Index (BMI) ≥25, high and low internalized weight bias, and insufficient activity (<60 min of moderate physical activity/week) to receive a 90-minute acceptance-based intervention workshop versus a multi-health behavior education condition prior to completing a 30-minute session of supervised, moderate intensity treadmill walking. Heart rate, self-reported perceived exertion and affect will be assessed throughout physical activity. For Phase 2, all participants from Phase 1 will receive a two-week physical activity prescription consistent with National Guidelines (150 minutes moderate intensity aerobic physical activity, recommended in 30-minute bouts) to determine the effect of treatment condition on subsequent adherence to physical activity. Physical activity adherence will be monitored with Actigraphy and Ecological Momentary Assessment (repeated daily surveys via smartphone) will be used to evaluate participant self-efficacy, intention, motivation for physical activity in near real-time.

Official Title
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Improving the Experience of Exercise Among Individuals With Internalized Weight Bias Using Acceptance-based Strategies

Conditions
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Overweight and Obesity

Intervention / Treatment
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* Behavioral: Acceptance and Commitment
* Behavioral: Multi-Health Behavior


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-60 years old, BMI 25-40 kg/m2 insufficiently active (<60 minutes of moderate intensity activity per week). High/low internalized weight bias Access to personal smartphone device and willing to download free smartphone app for data collection Exclusion Criteria: Comorbid issues that might interfere with ability to engage in physical activity Factors that would influence ability to complete study protocol (e.g., cognitive, psychological) medication that would affect heart rate (e.g., beta blocker), women who are nursing or pregnant

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Acceptance-based<br>This 90-minute one-on-one intervention will provide psychoeducation and experiential training on the use of acceptance-based strategies for physical activity. | Behavioral: Acceptance and Commitment<br>* During the 90-minute, one-on-one interventionist led session, participants will learn three inter-related acceptance-based techniques tailored for coping with physical discomfort and negative affect during physical activity. (1) cognitive defusion (i.e., disentangling physical sensations and thoughts from behavior), (2) acceptance (i.e., increasing willingness to experience unpleasant physical sensations/negative affect without trying to change or control them), and (3) valued action (i.e., evaluating the role of physical activity as a valued behavior). Participants will be taught these techniques via didactic instruction, metaphors, and experiential activities. All participants will receive a two-week physical activity prescription based on national guidelines recommending 150 minutes of at least moderate intensity physical activity per week.<br>|
| Sham Comparator: Multi Health Behavior<br>This 90-minute one-on-one intervention will provide psychoeducation on physical activity as one of several interconnected health behaviors. | Behavioral: Multi-Health Behavior<br>* The multi health behavior condition will include didactic material focused broadly on healthy lifestyle recommendations including physical activity. It will also emphasize that physical activity is one of several interconnected health behaviors including balanced diet, sleep, stress management. All participants will receive a two-week physical activity prescription based on national guidelines recommending 150 minutes of at least moderate intensity physical activity per week.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in perceived exertion | Assessed using the Borg Ratings of Perceived Exertion-Participants are prompted verbally to rate their exertion on a scale ranging from 6 (no exertion at all) to 20 (maximum exertion) every 5 minutes. | Every five minutes during 30-minute treadmill session | 
| Change in affect | Assessed using the Feeling Scale --This single-item measure assesses how participants feel 'at the present moment' on an 11-point scale ranging from -5 (very bad) to +5 (very good)), administered every 5 minutes during PA | Every five minutes during 30-minute treadmill session | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physical Activity Adherence | For two weeks following the intervention condition, physical activity will be objectively measured using the ActiGraph GT9X Link. This device, worn on the non-dominant wrist, has been previously validated to assess movement and associated energy expenditure. Minute-by-minute data will be analyzed to determine the amount of time spent in bout-related moderate intensity PA (≥ 3 METs, ≥10 min), metrics to increase the likelihood of capturing 'purposeful' PA | Daily for 14 days | 
| Exercise self-efficacy, intention, motivation | Using the Lifedata platform which includes the RealLife EXP application that can be downloaded onto participants' smartphones, participants will be prompted via vibration and audible tone to complete EMA surveys on self-efficacy, intention, and motivation for PA. Items are adapted from validated measures used in the physical activity literature. Participants will be prompted to complete a survey semi-randomly near four anchor times throughout the day, with 90 minutes to respond. | Four times per day for 14 days |