Influence of Fatigue on Tackling Technique in Rugby League Players

Abstract

This study investigated the influence of fatigue on tackling technique in rugby league players and determined the relationship between selected physiological capacities and fatigue-induced decrements in tackling technique. Eight rugby league players underwent a standardized one-on-one tackling drill in a 10-m grid. Players performed the one-on-one tackling drill before strenuous exercise and following game-specific repeated-effort exercise of progressively increasing intensities (corresponding to moderate, heavy, and very heavy intensity) in order to induce fatigue that was representative of match conditions. Video footage was taken from the rear, side, and front of the defending player. Tackling technique was objectively assessed using standardized technical criteria. In addition, all players underwent measurements of standard anthropometry (height, body mass, and sum of 7 skinfold measurements), speed (10-, 20-, and 40-m sprint), muscular power (vertical jump), agility (L run), and estimated maximal aerobic power (o₂max multistage fitness test). A progressive increase in total repeated-effort time, heart rate, blood lactate concentration, and ratings of perceived exertion occurred throughout the repeated-effort protocol, demonstrating a progressive increase in intensity and fatigue. Fatigue resulted in progressive reductions in tackling technique. Players with the best tackling technique in a nonfatigued state demonstrated the greatest decrement in tackling technique under fatigued conditions. In addition, a significant association was observed between estimated o₂max (r = −0.62) and agility (r = 0.68) and fatigue-induced decrements in tackling technique. From a practical perspective, these findings suggest that strength and conditioning programs designed to develop endurance, change of direction speed, and anticipation skills may reduce fatigue-induced decrements in tackling technique. Furthermore, any defensive drills designed to improve tackling technique should be performed before and under fatigue.