Physical Activity Choices Everyday

Study Overview
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Brief Summary
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This study aims to test two strategies for weight loss maintenance. It involves two phases, a weight loss phase and a maintenance phase. During Phase I (the weight loss phase), participants will receive a 16-week, Web-based behavioral weight loss program that involves access to weekly weight loss information and weekly personalized feedback on diet, activity, and weight loss goals. Individuals who lose at least 5% of their initial body weight during this program, will be invited to participate in Phase II. During Phase II, two 4-month treatments for weight loss maintenance will be tested. At the beginning of Phase II, participants will be randomly assigned to one of the two maintenance programs: (1) a behavioral maintenance program that involves in-person group meetings plus daily exercises in which information about a healthy lifestyle is reviewed or (2) a behavioral maintenance program that involves in-person group meetings plus daily exercises in which descriptions of positive future events are reviewed. Throughout the study, participants will complete assessments that examine the effects of the interventions on delay discounting, physical activity, weight, and other important health and psychosocial outcomes.

Official Title
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Is Long-term Maintenance Worth the Wait? Using Real Time Data Capture to Examine Delayed Discounting as a Putative Target of Physical Activity Adherence in Weight Loss Maintenance Interventions

Conditions
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Obesity

Intervention / Treatment
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* Behavioral: Weight Loss Maintenance + Healthy Thinking
* Behavioral: Weight Loss Maintenance Treatment + Future Thinking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 18-70 Body Mass Index between 30-50 English Speaking Have a smartphone that can be used for study activities Exclusion Criteria: Report being unable to walk 2 blocks without stopping Are currently participating in weight loss treatment, have a history of bariatric surgery, or lost ≥5% in the past 6-months Are pregnant or plan to become pregnant within 1 year Report a heart condition, chest pain during periods of rest or activity, or loss of consciousness on the Physical Activity Readiness Questionnaire Report a medical condition that could jeopardize their safety in a weight control program with diet and exercise guidelines History of or current traumatic brain injury, dementia or Alzheimer's disease; a history of Multiple Sclerosis, or other neurological disorders Report conditions that, in the judgment of the PI, would render them unlikely to follow the protocol (e.g., relocation, dementia, unable to read and write in English) Have no Internet access or unwilling to use personal smartphone for study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Behavioral Weight Loss Maintenance + Healthy Thinking<br>Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive a 4-month behavioral weight maintenance intervention consisting of 7 sessions that focus on evidence-based weight management strategies focused on diet, exercise, and behavioral skills. In this treatment, participants will be asked to read short passages related to nutrition and a healthy lifestyle through our study website twice a day for the duration of treatment. | Behavioral: Weight Loss Maintenance + Healthy Thinking<br>* Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive a 4-month behavioral weight maintenance intervention consisting of 7 sessions that focus on evidence-based weight management strategies focused on diet, exercise, and behavioral skills. In this treatment, participants will be asked to read short passages related to nutrition and a healthy lifestyle through our study website twice a day for the duration of treatment.<br>|
| Experimental: Behavioral Weight Loss Maintenance Treatment + Future Thinking<br>Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive a 4-month behavioral weight maintenance intervention consisting of 7 sessions that focus on evidence-based weight management strategies focused on diet, exercise, and behavioral skills. In this treatment, participants will create descriptions of upcoming positive events and will be asked to read short passages through our study website at least twice a day for the duration of treatment. | Behavioral: Weight Loss Maintenance Treatment + Future Thinking<br>* Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive a 4-month behavioral weight maintenance intervention consisting of 7 sessions that focus on evidence-based weight management strategies focused on diet, exercise, and behavioral skills. In this treatment, participants will create descriptions of upcoming positive events and will be asked to read short passages through our study website at least twice a day for the duration of treatment.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weekly Moderate-Vigorous Physical Activity Minutes, Accelerometry | Change in weekly minutes of moderate to vigorous physical activity measured via a waist worn accelerometer during the Phase II maintenance program. At each assessment time point, participants were instructed to wear the accelerometer on their right waist during all waking hours for 7 days. Participants with a minimum of 600 min of valid daily wear time for at least 4 days were included in reported outcomes. | Phase II baseline to 1 month, 2 months and 4 months (end of treatment) | 
| Delay Discounting (Adjusting Amount Task) | Change in delay discounting measured using the Adjusting Amount task during the Phase II maintenance program. Delay discounting refers to the decline in the present value of a reward with delay to its receipt. The Adjusting Amount task identifies an individual's discount rate, which reflects how much they devalue future rewards. In the task, participants are presented with a choice between a smaller, immediate (hypothetical) monetary reward and a larger, delayed (hypothetical) monetary reward. Then, using a titration procedure, the delayed reward amount is adjusted based on the participant's choices to find the point at which they are indifferent between the two options (i.e., discounting rate). The discount rate is represented by k. A higher k value means a steeper discount rate, indicating a greater preference for immediate rewards and a higher devaluation of future rewards. | Phase II baseline to 1 month, 2 months and 4 months (end of treatment) | 
| Delay Discounting (Monetary Choice Questionnaire) | Change in delay discounting measured using the Monetary Choice Questionnaire (MCQ) task during the Phase II maintenance program. Delay discounting refers to the decline in the present value of a reward with delay to its receipt. The MCQ identifies an individual's discount rate, which reflects how much they devalue future rewards. In the task, each question asks participants to make a choice between a smaller, immediate (hypothetical) monetary reward and a larger, delayed (hypothetical) reward. Unlike the Adjusting Amount task, each MCQ question includes different combinations of delay periods and reward amounts that are not influenced by previous responses (i.e., delay periods and reward amounts are static and the same for each participant). The discount rate is represented by k. A higher k value means a steeper discount rate, indicating a greater preference for immediate rewards and a higher devaluation of future rewards. | Phase II baseline to 2 months and 4 months (end of treatment) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight | Weight change from end of Phase 1 weight loss program to end of Phase II maintenance program | 4 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Weight Loss Maintenance