Knight, J.; Russell, M.; Cunningham, D.; Waldron, M.; Cook, C.; Kilduff, L.

Objective: To assess the effect of morning resistance exercise on afternoon physical and cognitive performance in male rugby union players. Methods: On two occasions (randomised, crossover design), 25 male rugby union players completed morning physical (countermovement jump, 40 m linear sprint) and cognitive (rapid visual information processing; spatial working memory; paired associates of learning) assessments. Control (passive rest) or intervention (barbell back squat, 3 x 3 repetitions at 85% of one repetition maximum and barbell squat jump, 5 x 3 repetitions at 40% one repetition maximum) trials were implemented 5.5 h before afternoon assessments. Results: Differences between morning and afternoon assessments were found in sprinting performance following intervention for 30 m fly (-0.08 {+/-} 0.13s, P = 0.001, ES: -0.75) and 40 m (-0.12 {+/-} 0.17 s, P = 0.004, ES: -0.62) relative to control (0.03 {+/-} 0.07 s, 0.01 {+/-} 0.09 s, 30 m fly and 40 m, respectively). Afternoon countermovement jump flight time improved following intervention compared to control (2% vs. 0%, P = 0.012). Delta analysis discovered significant differences from morning to afternoon in intervention (0.385 ms {+/-} 0.053) but not control (0.405 ms {+/-} 0.057). No changes were found for cognitive assessments (P>0.05). Conclusion: Morning lower body resistance exercise, incorporating a combination of high intensity and ballistic exercises, was an effective morning strategy to improve afternoon markers of physical but not cognitive performance in male rugby union players.