This randomized controlled trial evaluated whether structured exercise during school recess could improve observable classroom attention-related behavior in primary school children and whether the effects differed between grade levels.
A total of 144 third- and fifth-grade students were randomly assigned to one of three groups: high-intensity interval training (HIIT), moderate-intensity continuous training (MICT), or routine recess activity. The intervention lasted 6 weeks and was conducted three times per week during scheduled school recess. Each structured exercise session lasted 15 minutes, including warm-up, a 9-minute main exercise component, and cool-down.
Observable classroom attention-related behavior was assessed before and after the intervention using an automated video-based behavioral analysis system. The system evaluated observable indicators including head posture, eye gaze, eye opening or closing, and facial detection persistence. The study compared changes among the three groups and examined whether the effects of HIIT and MICT differed between third- and fifth-grade students.