Impact of Activity Trackers on Increasing Physical Activity

Inactivity is associated with weight gain and development of chronic illnesses.  Health care experts believe activity trackers might motivate sedentary adults become more active.  However, research supporting this is limited and vitiated by small non-randomized studies without long-term follow-up.  This study aimed to address these limitations. 

Participants, with BMI ≥ 28 and moderate and severe chronic illness were randomized to either Activity Tracker Only (ATO, N = 474) or Activity Tracker plus Coaching (AT+C, N = 473).  Males composed 16% of the sample, average age = 43 and average BMI was 36.

Exercise Readiness (ER) was a continuous covariate.  Assessment occurred at baseline, 3-months, 6-months, and 12-month follow-up.  Outcomes included discontinuation, step count, weight, QOL, absenteeism, and health care utilization and costs.  An accelerated failure-time survival analysis assessed discontinuation and Hierarchical Linear Modeling assessed outcomes. 

Discontinuation was high (25% at 1-week and >50% at 6-months).  AT+C ( =6-mo) and high ER (RR = .23) reduced discontinuation compared to ATO ( =4.5-mo).  AT+C participants increased steps by 1,503 compared to ATO who increased by 537.  More AT+C than ATO participants lost 5 pounds or more.  ER accounted for 27% of activity increase.  There were no significant findings for QOL, missed workdays, health care utilization, or costs.

Although activity trackers have potential to facilitate increased daily physical activity, the trackers alone will not steer the change.  Instead, successful use and health benefits related to these devices will depend on the design of engagement strategies such as educational coaching and social reinforcement.