Effects of a recess-based ocular muscle regulation training program on visual function in adolescents: a school-based controlled study

Objective This study aimed to investigate the effects of a 16-week recess-based ocular muscle regulation training program (OMRTP) on uncorrected visual acuity (VA) and noncycloplegic spherical equivalent (SE) in adolescents. Methods This school-based controlled study enrolled Grade 10–11 students (U15–U16; n = 200) from Huzhou No. 2 High School in Huzhou, China. Students were assigned at the class-cluster level within the same school to an experimental group (EG, n = 100) or a control group (CG, n = 100). The experimental group completed a 16-week recess-based OMRTP, whereas the control group received routine vision health education only. VA and noncycloplegic SE were assessed at baseline (week 0) and post-intervention (week 17). Intervention effects were evaluated using linear mixed-effects models within a difference-in-differences (DiD) framework. Results Baseline VA and SE were comparable between groups (all P > 0.05). For SE, the EG demonstrated more favorable short-term functional shifts in noncycloplegic SE relative to the CG across age strata and eyes (DiD: U15 left 0.318 D, right 0.358 D; U16 left 0.268 D, right 0.210 D; all P < 0.001). For VA, the EG showed greater improvements than the CG across age strata and eyes (DiD: U15 left 0.115, right 0.074; U16 left 0.156, right 0.105; all P < 0.05). Overall, mixed-effects models confirmed a significant group × time interaction for both SE ( F = 62.08, P < 0.001) and VA ( F = 42.03, P < 0.001). Conclusions A 16-week recess-based OMRTP was associated with improvements in uncorrected visual acuity and short-term functional changes in noncycloplegic spherical equivalent refraction among adolescents.