Exercise interventions may improve visual function and slow the structural progression of myopia in children and adolescents, although intervention characteristics appeared to influence treatment effects.
Investigators conducted a PRISMA-compliant systematic review and meta-analysis registered in PROSPERO, searching the CNKI, Wanfang, PubMed, and Web of Science databases to identify 31 randomized controlled trials involving 9,892 pediatric participants. They evaluated exercise interventions—including ball sports, mind-body exercises, visual training, and outdoor activities—compared with control interventions. Functional outcomes included dynamic and static visual acuity, while structural outcomes included refractive error and axial length.
Across the pooled analysis, exercise was associated with moderate improvements in both dynamic and static visual acuity, a modest improvement in refractive error, and reduced axial length elongation. Among the structural outcomes, axial length demonstrated low heterogeneity, indicating consistent effects across the studies.
Subgroup analyses suggested that intervention characteristics modified some functional outcomes. Greater improvements in dynamic visual acuity were observed among students in grades one through three with vision training interventions, programs delivered four to six times weekly, intervention durations of 120 to 300 minutes per week, and interventions conducted in combined indoor-outdoor settings. Static visual acuity improvements were greater with ball sports and mind-body exercises, intervention frequencies of one to three sessions weekly, and intervention durations of 120 to 300 minutes per week.
To explore the substantial heterogeneity observed in the functional outcomes, the investigators performed multivariable meta-regression analyses. Following adjustment, intervention setting remained the only independent factor associated with improvements in dynamic visual acuity, whereas differences among exercise modalities were attenuated. No moderator demonstrated a stable independent association with static visual acuity following adjustment.
The investigators acknowledged several limitations. Functional visual outcomes exhibited substantial heterogeneity across studies, and relatively few trials evaluated refractive error and axial length, limiting more detailed analyses of structural outcomes. In addition, all included studies were conducted in China, potentially limiting generalizability to other patient populations. The investigators noted the possibility of publication bias and emphasized the need for additional high-quality studies with longer follow-up to confirm the durability of the observed effects.
The findings suggested that exercise may complement existing strategies for myopia prevention and management in children and adolescents, particularly by improving visual function and inhibiting axial elongation. However, further studies are needed to determine the optimal exercise strategies and to clarify their long-term effects on structural myopia progression.
"[E]xercise interventions represent a promising adjunctive strategy for the comprehensive prevention and management of myopia in children and adolescents," wrote lead study author Jiacheng Ren, of the School of Sports Training at Wuhan Sports University in China, and colleagues.
The study authors reported no conflicts of interest.
Source: BMC Pediatrics