The Effectiveness of Online Exercise on Physical Activity, Motor Function, and Mental Health: Systematic Review and Meta-Analysis.

Background: Regular engagement in physical activity and exercise is associated with a multitude of physical and mental health benefits. Hence, it has been widely encouraged as a measure by which to combat somatic and psychological ailments. In view of the technical progress, the aging society and the public life restrictions issued during the COVID-19 pandemic, the delivery of interventions using digital devices has become highly popular. Objective: This systematic review and meta-analysis aimed to examine the effects of online exercise programs on physical activity (PA), motor performance, and mental health. Methods: Two independent investigators performed a systematic literature search, using PubMed, Cochrane Library, and Google Scholar. Randomized controlled trials assessing the effects of online exercise (OE) versus no exercise or face-to-face exercise (FFE) in healthy adults were included. Effect sizes (standardized mean difference [SMD]) were pooled using robust variance estimation. The quality of the included studies was assessed by 2 independent reviewers applying the PEDro scale, and publication bias was checked by means of funnel plots. To determine the certainty about the evidence, the results were rated by means of the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) criteria. Results: A total of 18 articles with moderate to high methodological quality (7/10 points on the PEDro scale), including a total of 3571 participants, were identified. Visual inspection of funnel plots provided indications of a publication bias for 2 out of 16 outcomes. According to the meta-analysis, OE was superior to no exercise regarding strength (SMD=0.61, 95% CI 0.06 to 1.15, n=5 studies), balance (SMD=0.52, 95% CI 0.06 to 0.99, n=4 studies), endurance (SMD=0.85, 95% CI -0.01 to 1.70, n=5 studies), PA (SMD=0.46, 95% CI 0.05 to 0.87, n=5 studies), depression (SMD=1.08, 95% CI -0.01 to 2.16, n=4 studies), mood or emotion (SMD=0.47, 95% CI 0.05 to 0.90, n=5 studies), mental well-being (SMD=0.79, 95% CI 0.06 to 1.52, n=4 studies), and self-efficacy (SMD=1.1, 95% CI 1.03 to 1.17, n=3 studies). Compared to FFE, OE was noninferior (P>.05) except for gait speed which improved more following FFE (SMD=0.25, 95% CI 0.24 to 0.26, n=2 studies). The certainty about the evidence (GRADE criteria) was low to moderate for all comparisons. Conclusions: OE represents an effective strategy to improve PA, physical function, and mental health in healthy adults and may hence help combat physical inactivity. However, despite the encouraging findings, some limitations need to be tackled before drawing definitive conclusions. These, inter alia, include a small total number of studies and substantial between-trial heterogeneity for some outcomes. Furthermore, as this review focused on healthy adults, future research examining other populations (eg, children and adolescents) is needed.