ArticleBMC medicine2025
Smartwatch-monitored physical activity and myopia in children: a 2-year prospective cohort study.
Article in BMC medicine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers, 3 of them syntheses that pooled it.
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Who cites it
9 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Impact of exercise on myopia in children and adolescents and its modifying factors: a systematic review and meta-analysis.BMC pediatrics · 2026Pooled it
- Exercise and visual training interventions for myopia in children and adolescents: a systematic review with a focus on near-far accommodation.Frontiers in public health · 2026Pooled it
- Comparative effectiveness of outdoor and exercise interventions for myopia control in children and adolescents: a systematic review and network meta-analysis of randomized clinical trials.Frontiers in public health · 2026Pooled it
- Analysis of the Association Between Weight Status and Myopia in Children and Adolescents and Development of a Screening Model Based on Body Fat Percentage.Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) · 2026Article
- Identifying and Managing Pre-Myopia: A Narrative Review.Clinical ophthalmology (Auckland, N.Z.) · 2026Review
- Physical activity for the co-prevention of myopia and obesity in children and adolescents: a scoping review.Frontiers in public health · 2026Article
- Prevalence of insufficient outdoor activity and caregiver-related correlates among school-aged children in Beijing, China: a cross-sectional analysis.Frontiers in public health · 2026Article
- Lifestyle and environmental risk factors for myopia in children: Evidence from a large-scale cross-sectional study in Shandong, China.PloS one · 2026Article
- Time outdoors and the prevention of myopia: School-based implementation works.Taiwan journal of ophthalmologyReview
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13 authors.
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Abstract
backgroundWhile outdoor time's protective role against myopia is established, the relationship between physical activity (PA) and myopia development remains unclear. This study aimed to determine the impact of PA on myopia in children.
methodsIn this prospective, school-based cohort study conducted in Shanghai from 2016-2018, children aged 6-9 years from 24 primary schools wore smartwatches for 1 year to record activity intensity and environmental status (indoor/outdoor). Activity load was calculated as a weighted sum of time spent in light (1 ×), moderate (2 ×), and vigorous (3 ×) activities. Myopia shift was measured by 2-year changes in spherical equivalent (SE) and axial length (AL). Limited myopia progression was defined as myopic shift ≤ -0.50 D over 2 years.
resultsAmong 4306 participants (mean age 7.3 ± 0.6 years; 47.1% girls), mean daily activity times indoors were 134.26 ± 31.99, 9.05 ± 3.34, and 2.63 ± 2.71 min for light, moderate, and vigorous activities respectively, with corresponding outdoor times of 59.10 ± 17.71, 12.64 ± 4.79, and 2.21 ± 1.11 min. Activity load showed protective associations in both environments, stronger outdoors (β = 0.18; 95% CI, 0.10-0.27; p < 0.001) than indoors (β = 0.06; 95% CI, 0.003-0.12; p = 0.037). Children in the highest quartile of indoor activity (≥ 3.02 weighted hours/day) showed 22% higher odds of limited myopia progression (adjusted OR = 1.22; 95% CI, 1.00-1.50; p for trend = 0.048), while those with outdoor activity ≥ 1.47 weighted hours/day demonstrated 34-77% higher odds (adjusted OR: Q3 = 1.34, 95% CI 1.01-1.80; Q4 = 1.77, 95% CI 1.32-2.36; p for trend < 0.001). Outdoor activity load was particularly protective in non-myopic children (β = 0.15; 95% CI, 0.07-0.23; p < 0.001) and those with daily outdoor time < 120 min (β = 0.22; 95% CI, 0.11-0.33; p < 0.001), while indoor activity load was protective in Grade 2 students (β = 0.11; 95% CI, 0.03-0.20; p = 0.009) and children with ≥ 120 min of outdoor time (β = 0.23; 95% CI, 0.07-0.39; p = 0.006).
conclusionsActivity load, integrating both time and intensity of PA, shows significant protective associations with myopic shift in both indoor and outdoor environments. This protective effect exists independent of light exposure, suggesting that PA might offer additional benefits for myopia prevention beyond the known effects of outdoor time.
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