Female Teens Step It Up with the Fitbit Zip: A Randomized Controlled Pilot Study

Abstract

Physical inactivity is a global pandemic. Six percent of all deaths globally (approximately 3.2 million people) are the result of insufficient physical activity, and 80% of adolescents worldwide do not get the recommended levels of daily physical activity. Depression is a major cause of disability worldwide and is a significant disease of burden for most age groups. Female adolescents are more than twice as likely to experience depressive symptoms as their male counterparts. The primary purpose of this randomized controlled pilot study was to determine if the use of electronic activity monitors, specifically Fitbit Zips, and daily step goals would increase physical activity participation in female adolescents. The secondary purpose was to determine if participation in a 12-week intervention using Fitbit Zips together with step goals would reduce depressive symptoms in female adolescents. The tertiary purpose was to determine the feasibility of recruiting and retaining female adolescents (80% or more) in the study and having them adhere to the research protocol. There were no available research studies examining physical activity and depressive symptoms in female adolescents using Fitbit Zips as an intervention to increase physical activity and decrease depressive symptoms. A convenience sample of 44 female adolescents from two church youth groups in the southeastern United States participated in the study. The mean age of the participants was 16.6 years. Psychosocial variables such as self-efficacy, social support, and commitment to a plan of action were assessed. Using mixed model analysis, no significant differences (p = .678) were found between the experimental (Fitbit-E) and control groups (Fitbit-C) on average median steps per day. The Fitbit-C group had 6,088.3 (SE = 668.6) average median steps per day at baseline, but only had 2,783.7 (SE = 698) average median steps per day at posttest. The Fitbit-E group had a lesser decline with 6,279.1 (SE = 661) average median steps per day at baseline and 4,339.4 (SE = 728) average median steps per day at posttest. Both groups’ depression scores, as measured by the CES-D, decreased from pretest to posttest, indicating an improvement in depressive symptoms. However, the difference between the two groups on depression scores was not statistically significant (p = .425). Post hoc pairwise comparisons yielded statistically significant decreases in depression scores for the Fitbit-C group (p = .002) and for the Fitbit-E group (p < .001) from pretest to posttest. Additionally, 42 out of 44 participants (95%) completed final CES-D surveys, and 35 out of 44 (79.5%) had some final step count data at post-test. Therefore, it was feasible to recruit and retain 80% of the participants in this RCT pilot study, and they did adhere to the protocol. This study helps bring to light the importance of promoting physical activity and assessing for depressive symptoms in the female adolescent population. Although there were no significant differences between the experimental and control groups on depressive symptoms for the 12-week intervention period, within each group there were significant decreases in depressive symptoms. The results from this study provide the groundwork to further investigate the impact of EAMs on physical activity and depressive symptoms in female adolescents.