Effectiveness of an Activity Tracker- and Internet-Based Adaptive Walking Program for Adults: A Randomized Controlled Trial

Abstract

Background: The benefits of physical activity are well documented, but scalable programs to promote activity are needed. Interventions that assign tailored and dynamically adjusting goals could effect significant increases in physical activity but have not yet been implemented at scale.

Objective: Our aim was to examine the effectiveness of an open access, Internet-based walking program that assigns daily step goals tailored to each participant.

Methods: A two-arm, pragmatic randomized controlled trial compared the intervention to no treatment. Participants were recruited from a workplace setting and randomized to a no-treatment control (n=133) or to treatment (n=132). Treatment participants received a free wireless activity tracker and enrolled in the walking program, Walkadoo. Assessments were fully automated: activity tracker recorded primary outcomes (steps) without intervention by the participant or investigators. The two arms were compared on change in steps per day from baseline to follow-up (after 6 weeks of treatment) using a two-tailed independent samples t test.

Results: Participants (N=265) were 66.0% (175/265) female with an average age of 39.9 years. Over half of the participants (142/265, 53.6%) were sedentary (<5000 steps/day) and 44.9% (119/265) were low to somewhat active (5000-9999 steps/day). The intervention group significantly increased their steps by 970 steps/day over control (P<.001), with treatment effects observed in sedentary (P=.04) and low-to-somewhat active (P=.004) participants alike.

Conclusions: The program is effective in increasing daily steps. Participants benefited from the program regardless of their initial activity level. A tailored, adaptive approach using wireless activity trackers is realistically implementable and scalable.

Trial registration: Clinicaltrials.gov NCT02229409, https://ichgcp.net/clinical-trials-registry/NCT02229409 (Archived by WebCite at http://www.webcitation.org/6eiWCvBYe).

Keywords: RCT; adaptive; effectiveness; intervention; physical activity; walking.

Conflict of interest statement

Conflicts of Interest: JP and NC are full-time employees of MeYou Health and own stock in Healthways Inc, the parent company of MeYou Health. WB, ML, GJ, H-CY, JC, and NS are faculty or employees of the Johns Hopkins University and were paid through an institutional consulting agreement with Healthways for work in designing the study and analyzing the data.

Figures

Figure 1

Examples of text messages participants can opt to receive (left) and reward notifications on the main website (right).

Figure 2

Sample participant steps and goals (actual steps taken are represented by blue bars with an associated trend line and surrounding confidence band; light blue bars indicate run-in data collection and follow-up periods; goals provided to users are represented in red; black arrow markers indicate the direction and magnitude of the random adjustment applied). These random adjustments averaged 2945 steps in either direction. Run-in data are presented here but are not used by the algorithm to preserve generalizability.

Figure 3

CONSORT diagram.