Despite tremendous adoption of wearable fitness trackers by adults, it is unclear if they affect physical activity engagement or motivation. In a paper published in the Journal of Sports Sciences, Dr. Kayla Nuss, Klein Buendel Scientist, and her research collaborators reported on a study to examine the combined effects of motivational interviewing and wearable fitness trackers on motivation and physical activity in inactive adults.

The authors hypothesized that combining a wearable fitness tracker (such as a FitBit®) with an effective intervention (motivational interviewing), would positively influence both motivation and physical activity. To test the hypothesis, a 12-week randomized controlled trial was conducted with 40 adults who did not meet physical activity recommendations. The four comparison groups were: (1) physical activity education only (educational control) with 10 participants, (2) use of a wearable fitness tracker (WFT) with 10 participants, (3) bi-weekly motivational interviewing sessions with 10 participants, or (4) both motivational interviewing and WFT (WFT+) with 10 participants.

Motivation and physical activity were measured though an online survey and actigraphy (a method to objectively estimate physical activity) pre- and post-intervention. Both the WFT+ and motivational interviewing groups scored higher in autonomy, competence, and relatedness for physical activity compared to the control group, which is associated with higher quality, or more autonomous forms of motivation. Further, both groups did show improvements in autonomous forms of motivations (such as interest or enjoyment) and decreased controlled forms of motivation (such as pressure or reward). Detailed descriptions of the study’s methods, recruitment efforts, measures, data analysis, outcomes, and limitations can be found in the Journal of Sports Sciences publication.

The authors detected no changes in physical activity. High autonomous motivation at baseline predicted higher post-intervention physical activity in the WFT+ group, but predicted lower post-intervention physical activity in the WFT group. The results of the study suggest that motivational interviewing alone or with a wearable fitness tracker can improve basic psychological needs and autonomous forms of motivation for physical activity, but not physical activity participation. The authors conclude that individual differences in motivation at baseline may moderate the effect of a wearable fitness tracker on physical activity. The findings add to the growing body of evidence that wearable fitness trackers can have some positive effect on adult’s physical activity.

This research was supported by Colorado State University Department of Health and Exercise Science (Dr. Kayla Nuss, Project Director). Collaborating authors included Ms. Kristen Moore from the University of Southern California; Dr. Tasha Marchant from the University of Colorado Health Sciences Center; Dr. Jimikaye Beck Courtney from the University of North Carolina-Chapel Hill; and Ms. Kathryn Edwards, Dr. Julia Sharp, Dr. Tracy Nelson, and Dr. Kaigang Li from Colorado State University.