Acute Cognitive Effects of Brief Physical Activity Breaks After Lecture-Based Academic Activity in Undergraduate University Students: A Randomized Crossover Study

Background: Prolonged sitting during lecture-based academic activities may be accompanied by sustained attentional engagement and cognitive fatigue, with potential consequences for cognitive efficiency and broader psychological functioning. Physical activity breaks (PABs) represent a feasible strategy to interrupt sitting time within university timetables, yet evidence in higher-education settings remains limited, particularly regarding modality-specific effects. This randomized crossover study examined the acute effects of a 10 min PAB on attentional and executive functioning in undergraduate students and compared an outdoor physical activity break (OPAB) with an exergame-based PAB (PABEx) versus a no-break control (NPAB). Methods: Forty-two undergraduate students (26 males, 16 females; mean age = 22.78 ± 5.84 years) completed three weekly conditions in randomized order following two consecutive hours of seated lectures: NPAB (seated rest), OPAB (2 min warm-up, 6 min light-to-moderate walking, 2 min cool-down), and PABEx (2 min warm-up, 6 min Fruit Ninja Kinect, 2 min cool-down). Cognitive performance was assessed immediately after each condition using the Trail Making Test A-B (TMT A-B) and the Stroop Color-Word Test (SCWT). Results: Significant condition effects were found for TMT-A (χ2 = 53.976, p < 0.001), TMT-B (χ2 = 44.635, p < 0.001), TMT B-A (χ2= 10.841, p = 0.004), SCWT interference time (χ2 = 44.714, p < 0.001), and SCWT interference errors (χ2 = 23.211, p < 0.001). Post-hoc tests showed that both OPAB and PABEx were associated with better performance on TMT-A, TMT-B, and SCWT interference time versus NPAB (all Benjamini–Hochberg-adjusted p < 0.001); PABEx was associated with better TMT-A performance than OPAB (Benjamini–Hochberg-adjusted p = 0.047). TMT B-A decreased only for OPAB versus NPAB (Benjamini–Hochberg-adjusted p = 0.009). SCWT interference errors were lower for OPAB versus NPAB (Benjamini–Hochberg-adjusted p< 0.001) and for PABEx versus NPAB (Benjamini–Hochberg-adjusted p = 0.012). Conclusions: A 10 min PAB implemented immediately after a lecture-based academic activity was associated with more favorable post-condition attentional and executive performance in undergraduate students compared with a passive no-break condition. OPAB and PABEx yielded broadly comparable benefits across executive outcomes, whereas PABEx showed an additional advantage for TMT-A, suggesting a possible modality-specific effect on processing speed and visuoperceptual tracking. These findings support the integration of brief active breaks into university schedules as a pragmatic strategy to promote post-lecture cognitive efficiency during academically demanding periods. Trial registration: ClinicalTrials.gov, NCT07624084; retrospectively registered on 28 May 2026.