Pediatrics · Medical Literature
Digital health interventions for promoting physical activity among adolescents: a systematic review.
Abstract
The issue of insufficient physical activity in adolescents (defined by the World Health Organization as those aged 10-19 years) is a significant worldwide health concern, as 81% do not achieve the suggested levels of physical exercise. Although digital health interventions (DHIs) present promising scalable solutions, their actual performance in practical environments often falls short of anticipated outcomes. This systematic review provides a critical analysis of the existing research on digital strategies aimed at enhancing physical activity among adolescents, emphasizing the factors that contribute to their success, user engagement, and equitable access. This systematic synthesis compiles findings from scholarly articles released from 2020 to 2026. The primary outcome was physical activity, measured by daily step counts or minutes of moderate-to-vigorous physical activity (MVPA). Secondary outcomes included engagement, adherence, motivation, psychological factors, equity, and other health-related measures. We included randomized controlled trials, cohort studies, cross-sectional studies, mixed-methods studies, systematic reviews, and meta-analyses. By examining research on a range of digital health technologies-including wearable devices (e.g., fitness trackers, smartwatches), mobile applications, gamified platforms, chatbots, and AI-driven tools-the analysis integrates quantitative data with qualitative insights from co-design studies to provide comprehensive insight into the effectiveness, timing, and target audiences of digital interventions. Methodological quality and risk of bias were assessed using study-design-specific tools: RoB 2 for randomized controlled trials, ROBINS-I for non-randomized interventional studies, AMSTAR 2 for systematic reviews and meta-analyses, NOS for cohort and longitudinal studies, AXIS for cross-sectional studies, CASP for qualitative studies, and MMAT for mixed-methods studies. The results reveal a persistent disparity between effectiveness and user involvement: while 63% of the examined DHIs demonstrated positive results in their initial assessments, adherence levels dropped from 73% at the start to just 14% by the fifth month. (The 63% = 29/48 studies reporting a significant positive effect on PA. The adherence rates are from a single cohort study tracking device usage over time, not pooled across studies). The success of these interventions is not solely dependent on advanced technology but rather on the integration of three interconnected factors: (1) developmental suitability, where younger adolescents (approximately 10-13 years) are more responsive to playful, sensorimotor activities, whereas older adolescents (approximately 14-19 years) prefer goal-setting and tracking their own progress. (2) relational design, features like team challenges, empathetic AI characters, and customizable avatars can boost confidence by 50% and motivation by 120%; and (3) contextual relevance, data indicates that moderate to vigorous physical activity (MVPA) peaks between 5 and 8 p.m., highlighting the critical difference between screen time (which can hinder activity) and the frequency of physical engagement (which encourages it). Ongoing disparities in equity-such as digital literacy gaps exceeding 35% and reduced engagement among racial and ethnic minorities-emphasize the need for intentional structural and cultural alignment to prevent digital interventions from widening existing inequalities. Effective digital solutions prioritize the needs of adolescents rather than focusing solely on technology. They emphasize tailored experiences instead of fixed features, foster meaningful connections rather than relying on precise algorithms, and adapt to specific contexts instead of aiming for one-size-fits-all scalability. Future developments should shift away from merely measuring screen time and instead embrace approaches that are rich in experience, affirm individual identities, and promote social justice while incorporating physical activity into the everyday lives of young people. https://www.crd.york.ac.uk/PROSPERO/view/CRD420261415756.
Clinical relevance
Do digital health interventions (DHIs) — including mobile apps, wearable devices, AI-based tools, and gamified platforms — effectively promote physical activity (measured by daily step counts or minutes of MVPA) among adolescents aged 8–19, and what factors determine their success, user engagement, and equitable access? __SNAPSHOT__ {"studyDesign":"Systematic review (narrative synthesis; no quantitative meta-analysis performed) adhering to PRISMA 2020 guidelines; multiple study designs included (RCTs, cohort studies, cross-sectional studies, mixed-methods studies, prior systematic reviews, and meta-analyses)","setting":"International; not restricted to a single country or institution type; search conducted across PubMed, Web of Science, EBSCO, Scopus, Embase, Cochrane Library, ProQuest, and Google Scholar (supplementary)","sampleSize":"Number of included primary studies not reported in the abstract; the review incorporated literature published from 2020 to 2026, with six 2026 publications included (four online ahead of print, one fully published, one study protocol)","population":"Children and adolescents aged 8–19 years (primary focus on WHO-defined adolescents, ages 10–19); the age range was extended to 8 years to capture developmental transitions in late childhood and early adolescence","intervention":"Digital health interventions (DHIs) including, but not limited to, mobile health (mHealth) apps, AI-based tools, chatbots, wearable devices, gamified platforms, web-based platforms, social media, and telemedicine/telehealth modalities","comparator":"Varies by included study design (active comparators, usual care, or no intervention); not uniformly specified at the review level","primaryOutcome":"Physical activity, measured by daily step counts or minutes of moderate-to-vigorous physical activity (MVPA)","followUp":"Not uniformly reported; acknowledged in the review as a limitation (insufficient follow-up across included studies)","fundingSource":"Not reported in abstract or publicly available full-text excerpt"}
Key findings
Full quantitative pooled effect sizes, confidence intervals, and p-values are not reported in the abstract, and no meta-analysis was performed; these values therefore cannot be stated. Narratively, the review concludes that DHIs generally enhance adolescent physical activity levels, although effectiveness varies considerably across intervention types and study designs. The review identifies three interconnected factors that determine intervention success: (1) developmental suitability — younger adolescents (approximately ages 10–13) respond more favorably to playful, sensorimotor activities, whereas older adolescents (approximately ages 14–19) prefer goal-setting and progress-tracking features; (2) relational design — elements such as team challenges, empathetic AI characters, and customizable avatars were reported to boost confidence by 50% and motivation by 120% (source and methodology for these specific figures not further clarified in the abstract; interpret with caution); and (3) contextual relevance — MVPA was reported to peak between 5 and 8 PM, a finding the authors use to distinguish productive screen engagement from sedentary screen time. Adolescents demonstrated adequate engagement levels with DHIs. Pre-to-post MVPA changes were described as small. Secondary outcomes (engagement, adherence, motivation, psychological factors, and equity) were synthesized narratively. Adverse events and harms were not reported. NNT/NNH cannot be calculated from the available data.
Practice implications
This systematic review provides broad directional evidence that DHIs can modestly promote physical activity in adolescents, with effectiveness contingent on developmental appropriateness, relational design elements, and implementation context rather than on technological sophistication alone. The review explicitly addresses underserved considerations including equity gaps, digital health inequalities, adolescents with special health conditions, and technology dependency — important dimensions often absent from prior reviews. However, the absence of a meta-analysis, the heterogeneity of included study designs, and the lack of reported pooled effect sizes, confidence intervals, or p-values substantially limit the precision of conclusions. The inclusion of children as young as age 8 introduces a population mismatch with the stated adolescent focus, which may affect the generalizability of findings to the core target group. Adolescents from low-resource settings, those with disabilities, and those with limited digital access are acknowledged as inadequately represented. The review does not establish causality, and the magnitude of MVPA change (described as 'small') raises questions about clinical significance. Practice change based on this review alone is premature; it should be interpreted alongside higher-certainty meta-analytic evidence. Importantly, only the abstract was accessible for this summary, which limits full appraisal of methodological rigor, subgroup analyses, and the basis for specific quantitative claims (e.g., 50% confidence boost, 120% motivation increase). __LIMITATIONS__ No quantitative meta-analysis was performed, preventing pooled effect size estimation and limiting the strength of conclusions,Significant heterogeneity of included study designs (RCTs, cohort, cross-sectional, mixed-methods, prior systematic reviews) limits internal comparability,Review protocol was not prospectively registered (no PROSPERO registration reported for this Frontiers article), introducing risk of post hoc outcome selection,Restriction to English-language publications introduces selection bias and limits generalizability to non-English-speaking populations,Inclusion of children as young as age 8 creates population heterogeneity inconsistent with the review's stated adolescent focus,Insufficient follow-up duration across included studies acknowledged by authors; long-term sustainability of DHI effects not established,Several included 2026 studies were 'online ahead of print' or study protocols, potentially introducing immature evidence,Specific quantitative claims (e.g., 50% confidence increase, 120% motivation increase) are not supported by methodological detail in the abstract, warranting caution,Equity gaps and digital divide concerns are acknowledged but not formally analyzed or quantified,Funding source not reported, precluding assessment of potential industry influence,MVPA changes described as 'small,' raising questions about clinical versus statistical significance that are not formally addressed __BOTTOM_LINE_CATEGORY__ promising_but_preliminary __BOTTOM_LINE__ This systematic review provides directional evidence that digital health interventions modestly improve physical activity in adolescents, with effectiveness driven by developmental appropriateness, relational design, and implementation context rather than technology alone. However, the absence of meta-analytic pooling, heterogeneous study designs, lack of prospective protocol registration, and small reported effect sizes preclude definitive conclusions or immediate practice change. Clinicians may use these findings to informally counsel adolescents and families about DHI features most likely to promote engagement, while awaiting higher-certainty evidence.