Author(s): TSANG, W., YE, Z., CHOY, H.L.A., HA, K.K.A., CHAN, H.L., SUM, K.W.R., Institution: THE CHINESE UNIVERSITY OF HONG KONG, Country: HONG KONG, Abstract-ID: 982

Background
Physical literacy (PL) has been recognized as a holistic framework for promoting active and healthy lifestyles in children. Yet empirical evidence on classroom‑embedded interventions grounded in ecological dynamics remains limited, particularly in Hong Kong primary schools, where sedentary behavior is highly prevalent. This study examined the preliminary effects of an ecological dynamics intervention (EDI) integrating sit–stand desks, structured physical‑activity (PA) recess, and a brief nap on children’s PL and perceived well‑being.

Methods
118 primary school children (64 boys, 54 girls) from four classes were assigned to one of four arms for an 11-month longitudinal study (pre-, mid-, post-, and follow-up assessments): (1) EDI‑A (sit–stand desks + PA recess + nap); (2) EDI‑B (PA recess + nap); (3) EDI‑C (nap only); and (4) Wait‑list Control. Outcomes spanned four PL-related domains and perceived well‑being. Physical Competence: aerobic fitness (15 m PACER Test) and fundamental movement skills (CAMSA Test). Cognitive Function: sustained attention (PVT Test), working memory (N-back Test), and selective attention (AX-CPT Test). Daily Behavior: PA level (Actigraph GT3X+). Self-Reported Outcomes: perceived PL (PPLI), health-related quality of life (CHU9D), and daytime sleepiness (PDSS). Linear mixed models (LMMs) were used to test for Time × Group interactions, controlling for age and sex.

Results
Aerobic fitness improved significantly over time across all groups (p<.001), but no significant Time × Group interaction was found. fundamental movement skills showed no significant effects for time or group. Significant time effects were observed in cognitive outcomes, with improvements in N-back accuracy (p<.001) and AX-CPT reaction time (p<.001) for all groups, but without significant interactions. LMMs revealed significant Time × Group interactions for light (p=.011) and moderate physical activity (p<.001), with the EDI-B group generally demonstrating higher activity levels than other groups post-intervention. Daily MVPA and steps significantly declined over time (p<.001), irrespective of group. A significant Time × Group interaction was found for daytime sleepiness (p<.001); at post-test, the EDI-C group reported significantly less sleepiness than the control group (p=.008). Quality of life scores significantly decreased for all groups at the final follow-up (p<.001).

Conclusion
These findings showed that an integrated EDI can yield specific benefits, notably enhanced light-to-moderate physical activity from combining PA recess and naps, and a transient reduction in daytime sleepiness from naps alone. However, the universal decline in MVPA and quality of life highlights the impact of broader contextual factors (e.g., seasonal or academic pressures) and the need for strategies to bolster intervention maintenance. These results provide practical guidance to those researches aimed at promoting physical literacy in Hong Kong.