Can Smartphone Apps Increase Physical Activity? Systematic Review and Meta-Analysis (Preprint)

Abstract

BACKGROUND Smartphone apps are a promising tool for delivering accessible and appealing physical activity interventions. Given the large growth of research in this field, there are now enough studies using the “gold standard” of experimental design—the randomized controlled trial design—and employing objective measurements of physical activity, to support a meta-analysis of these scientifically rigorous studies. OBJECTIVE This systematic review and meta-analysis aimed to determine the effectiveness of smartphone apps for increasing objectively measured physical activity in adults. METHODS A total of 7 electronic databases (EMBASE, EmCare, MEDLINE, Scopus, Sport Discus, The Cochrane Library, and Web of Science) were searched from 2007 to January 2018. Following the Population, Intervention, Comparator, Outcome and Study Design format, studies were eligible if they were randomized controlled trials involving adults, used a smartphone app as the primary or sole component of the physical activity intervention, used a no- or minimal-intervention control condition, and measured objective physical activity either in the form of moderate-to-vigorous physical activity minutes or steps. Study quality was assessed using a 25-item tool based on the Consolidated Standards of Reporting Trials checklist. A meta-analysis of study effects was conducted using a random effects model approach. Sensitivity analyses were conducted to examine whether intervention effectiveness differed on the basis of intervention length, target behavior (physical activity alone vs physical activity in combination with other health behaviors), or target population (general adult population vs specific health populations). RESULTS Following removal of duplicates, a total of 6170 studies were identified from the original database searches. Of these, 9 studies, involving a total of 1740 participants, met eligibility criteria. Of these, 6 studies could be included in a meta-analysis of the effects of physical activity apps on steps per day. In comparison with the control conditions, smartphone apps produced a nonsignificant (P=.19) increase in participants’ average steps per day, with a mean difference of 476.75 steps per day (95% CI −229.57 to 1183.07) between groups. Sensitivity analyses suggested that physical activity programs with a duration of less than 3 months were more effective than apps evaluated across more than 3 months (P=.01), and that physical activity apps that targeted physical activity in isolation were more effective than apps that targeted physical activity in combination with diet (P=.04). Physical activity app effectiveness did not appear to differ on the basis of target population. CONCLUSIONS This meta-analysis provides modest evidence supporting the effectiveness of smartphone apps to increase physical activity. To date, apps have been most effective in the short term (eg, up to 3 months). Future research is needed to understand the time course of intervention effects and to investigate strategies to sustain intervention effects over time.

The impact of a gamified intervention on daily steps in real-life conditions: a retrospective analysis of 4800 individuals

“…Secondly, the results revealed that the total number of games played was negatively associated with the intervention effect, suggesting that shorter interventions could be more beneficial for behavior change. These results are in line with previous research [20,52] suggesting that digital interventions shorter than 3 months tend to yield greater benefits. It also suggests a « dose-response » relationship in inverted U shape, with an optimal "middle" to find.…”

Optimizing Internet Use during Adolescence: eHealth Solutions

“…The effect was less pronounced when these were combined with dietary interventions. 7 Smartphone apps have also shown good performance in weight control and obesity prevention programs. A meta-analysis of 12 studies on adolescents and adults showed significant reduction in weight (−1.07 kg, 95% confidence interval [CI]: −1.92 to −0.21) and body mass index (−0.45 kg/m 2 , 95% CI: −0.78 to −0.12) with the use of mobile apps; however, with nonsignificant effect on increase in physical exercise.…”

The effect of smartphone application interventions on physical activity level among university/college students: a systematic review protocol

“…Previous literature reviews provide evidence of promising results of smartphone applications for promoting PA behavior [21,22,23,24,25]. Evidence from nonrandomized controlled trials found that smartphone apps could either increase PA, decrease PA, or prevent PA decline [21].…”

“…Evidence from nonrandomized controlled trials found that smartphone apps could either increase PA, decrease PA, or prevent PA decline [21]. Romeo et al [25] conducted a subgroup analysis on healthy adult across all ages that resulted in a small, inconclusive and high heterogeneous result (mean difference= +649,54 steps per day, 95% CI -822.66 to 21221.74, I 2 80%). Heterogeneous and inconclusive results from previous systematic reviews could be attributable, in part, to various population.…”