Physical activity partners for women with cardiovascular disease risk: Proof-of-concept trial with daily assessment.

Objective: Risk for cardiovascular disease (CVD) increases sharply for women during midlife (aged 40-65). Physical activity (PA) is key during this time, though lack of social support is a primary barrier. The present study combined PA coaching with the formation of PA partnerships by pairing participants with each other for support during an 8-week behavioral PA intervention. This proof-of-concept study assessed feasibility, acceptability, and clinically significant change in the outcome and mediator of interest.

Method: Women in midlife with ≥ 1 risk factor for CVD (e.g., hypertension; N = 62, M_age = 52.6, M_BMI = 32.6 kg/m²) completed six weekly sessions with a PA coach, with assessment in Weeks 1 and 8; three sessions were joint meetings with their PA partner. They also completed daily ambulatory assessment and postintervention surveys. Data were collected in 2024 (NCT06350604).

Results: Recruitment (4.5 months), treatment adherence (97%), daily assessment compliance (84%), and retention (100%) all met or exceeded prespecified benchmarks, and sample characteristics showed strong representation from hard-to-reach groups (e.g., 20% household income < $50,000/year). Partners communicated on 47% of days (M = 3.5 times/week); PA increased by ∼500 steps/day from baseline (p < .01, d = 0.43) and 19% of participants increased by ≥ 2,000 steps/day. Acceptability was high (4.2/5) and ratings of PA-specific social support meaningfully increased (p < .001, d = 0.66).

Conclusion: Results demonstrate high acceptability and strong promise of partner-based PA intervention for improving cardioprotective behavior among women in midlife with elevated CVD risk. Thus, findings support larger scale testing with the inclusion of daily assessment, which can reveal mechanistic pathways linking social support to PA in daily life. (PsycInfo Database Record (c) 2025 APA, all rights reserved).