Protocol for stronger: A pilot factorial randomized trial testing adherence to a remotely-delivered strength training intervention among women in perimenopause

BACKGROUND: The menopausal transition is a key window for preventing musculoskeletal decline through strength training, yet fewer than 25% of midlife women meet guidelines. Scalable interventions are needed. METHODS: Stronger is a pilot randomized clinical trial evaluating a 12-week remotely delivered strength training program for perimenopausal women, followed by 12-week maintenance. Assessments occurred at baseline, 6, 12, and 24 weeks. Using a 2 × 2 + 1 factorial design, 90 participants were randomized to four intervention conditions or waitlist control. Analyses will test main and interaction effects of exercise schedule-distributed "snacks" (1-2 exercises, three times/day) versus consolidated "sessions" (five exercises, once/day), both twice weekly-and tracking simplicity (simplified versus detailed self-monitoring). Intervention participants received progressive overload training with sandbags, virtual office hours, and perimenopause education. All participants received protein guidance (1.6 g/kg/day). The primary outcome is 12-week adherence: exercises completed divided by 120 prescribed exercise opportunities (five exercises, three high-effort sets, twice weekly). Secondary outcomes include maintenance adherence, engagement, hamstring and quadriceps strength, sit-to-stand repetition maximum, step power, and 12-week waitlist retention. Exploratory outcomes include DXA body composition, functional performance, and psychosocial measures. Analyses will also assess changes and dropout among waitlist participants. RESULTS: Recruitment began in June 2025, data collection ended in February 2026, and analyses are ongoing. CONCLUSIONS: Stronger will provide preliminary evidence on whether strength snacks improve adherence and inform scalable digital strength training strategies to support strength, body composition, functional performance, and psychosocial outcomes in perimenopausal women and identify promising approaches for future definitive trials.