In this study insufficiently active adults with obesity will be assigned to either the Physical Activity for The Heart (PATH) intervention or an attention control group.

The United States' 2018 Physical Activity Guidelines recommend that American adults should achieve ≥150 min of moderate intensity physical activity (PA), 75 min of vigorous PA, or an equivalent combination of both moderate and vigorous physical activity (MVPA) weekly. Yet, adherence to these Guidelines is low, with 26% of adults with normal weight and 14% of adults with obesity attaining the minimum recommended PA levels. The low PA levels are associated with the rising prevalence of obesity and increase the relative risk of stroke, coronary heart disease, and diabetes by 60%2, 45%, and 30%, respectively. Since individuals with obesity are more vulnerable to cardiovascular disease (CVD) and its risk factors, weight loss is recommended. Yet, even without weight-loss, PA significantly reduces CVD risk. However, individuals with obesity face complex multifaceted barriers that reduce their engagement in PA.

Barriers to PA associated with obesity include stigma, shame, poor fitness, and low self-efficacy. These evoke fear of embarrassment and pain, contributing to aversion of PA. To mitigate these barriers, web-based PA programs targeting adults with obesity have been developed. Preliminary data suggest improved retention, but the effects on PA are heterogeneous. Limitations of these interventions include lack of human contact, 'one-size-fits-all' strategies, unmet weight-loss expectations, and generic content that fails to address the barriers associated with obesity. Researchers have reported that individuals with obesity prefer programs that are convenient, fun to engage in, and feature people who they can relate to in body size, fitness level, and age. Yet, there is a paucity of PA interventions intentionally designed to flexibly incorporate these preferences.

To address the limitations of previous interventions, the research team of this study designed the web-based Physical Activity for The Heart (PATH) intervention. PATH leverages openly accessible platforms, such as YouTube, to provide workout videos that match the specific preferences expressed in our formative studies and the extant literature. In developing PATH, the researchers employed an iterative bottom-up approach where the target population was engaged in the selection and rating of the workout videos. Then, highly rated workouts (≥3.5/5 stars) were vetted by the study team for content relevance and safety, and then curated on the PATH website in 3 intensity levels (beginner, intermediate, proficient) to foster gradual progression from low to high intensity PA. The researchers added backend features that enable a remote health coach to help users set their PA goals and select a PA regimen that is safe for their fitness level. Each PATH user has a personalized dashboard displaying their recommended workouts and progress towards their PA goals.

In this study, 88 insufficiently active adults with obesity will be assigned to either the PATH intervention or the attention control group for 6 months.

Inclusion Criteria:

• Regular access to the Internet
• BMI ≥30kg/m^2
• Successful self-monitoring of PA (≥4 days with ≥10hrs wear time) via waist worn Actigraph
• Non-adherence to the PA Guidelines (<150 min of MVPA/wk)

Exclusion Criteria:

• Pregnancy or intention to become pregnant within 6 months
• Mobility restrictions, or any condition that requires supervised PA (e.g., stroke)
• Individuals with history of heart disease, diabetes, or those who respond in affirmative to any question in the Physical Activity Readiness Questionnaire will be required to obtain Primary Care Provider (PCP) clearance before enrollment

Deidentified participant data will be made available for the main study outcomes. Other data from the questionnaires or other assessments may be available for sharing on a case by case basis.

Data will be made available for sharing one year after publication of study outcomes.

Individual participant data will be available for sharing with researchers who provide a methodologically sound proposal, in order to achieve aims in the approved proposal. Proposal should be directed to jacob.kariuki@emory.edu. To gain access, data requesters will need to sign a data access agreement.