Background
Direct-to-consumer mHealth devices are a potential asset to behavioral research but are rarely tested as intervention tools. This trial examined the accelerometer-based Fitbit tracker and website as a basis for a low-touch physical activity intervention.
Purpose
To evaluate, within a randomized controlled trial, the feasibility and preliminary efficacy of integrating the Fitbit tracker and website into a physical activity intervention for postmenopausal women.
Methods
Fifty-one inactive, postmenopausal women with BMI≥25.0 kg/m2 were randomized to a 16-week web-based self-monitoring intervention (N=25) or a comparison group (N=26). Those in the Web-Based Tracking Group received a Fitbit, an instructional session, and a follow-up call at 4 weeks. The comparison group received a standard pedometer. All were asked to perform 150 min/week of moderate-to-vigorous physical activity (MVPA). Physical activity outcomes were measured by the ActiGraph GT3X+ accelerometer.
Results
Data were collected and analyzed in 2013–2014. Participants were 60±7 years old with BMI=29.2±3.5 kg/m2. Relative to baseline, the Web-Based Tracking Group increased MVPA by 62±108 min/week (p<.01), MVPA in 10-min bouts by 38±83 min/week (p=.008), and steps by 789±1,979 (p=.01), compared to non-significant increases in the Pedometer Group (between-group p-values: .11, .28 and .30, respectively). The Web-Based Tracking Group wore the tracker on 95% of intervention days; 96% reported liking the website and 100% liked the tracker.
Conclusions
The Fitbit was well-accepted in this sample of women and was associated with increased physical activity at 16 weeks. By leveraging direct-to-consumer mHealth technologies that align with behavior change theories, researchers can strengthen physical activity interventions.