Effects of high-intensity interval training and moderate-intensity continuous training on classroom attention in fifth-grade students

Objective The aim was to examine how high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) differentially affect in-class attention among fifth-grade students, with the goal of informing evidence-based physical education curriculum design. Methods Seventy-two children aged 10–11 years were randomly assigned to three groups: HIIT, MICT, and a control group ( n = 24 each). The HIIT group completed a 6-week intervention with three 24-minute sessions per week (≥85% maximum heart rate (HRmax)), while the MICT group performed continuous running at 60–69% HRmax at the same frequency. The control group maintained regular school activities. Exercise intensity was monitored using Polar heart rate sensors. Attention was assessed pre- and post-intervention via an intelligent video-based system analyzing four sub-indicators: head posture, gaze direction, eye openness, and facial detection, along with an overall attention score. Data were analyzed using repeated-measures analysis of variance (ANOVA). Results Both HIIT and MICT significantly improved the overall attention score ( P < 0.01). The HIIT group increased from 0.39 ± 0.08 to 0.70 ± 0.14 (a 79.5% improvement), while the MICT group rose from 0.38 ± 0.10 to 0.67 ± 0.12 (a 76.3% improvement). The HIIT group demonstrated a significantly greater improvement than the MICT group ( P < 0.01). The control group showed minor gains (31.0%; P < 0.05). Sub-indicator analysis revealed that HIIT significantly enhanced head posture and gaze direction ( P < 0.01), while MICT primarily improved facial detection ( P < 0.01). Conclusion Both high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) demonstrated positive effects on the enhancement of children’s overall in-class attention. Notably, HIIT demonstrated superior overall effects and produced significantly greater improvements across multiple attention sub-dimensions compared with MICT. These findings provide empirical support for the incorporation of HIIT into school-based physical education curricula as an effective strategy for enhancing students’ cognitive performance.