• Physical demands of elite rugby league match-play and the subsequent impact on recovery

      Highton, Jamie M.; Twist, Craig; Oxendale, Chelsea (University of Chester, 2014)
      Whilst fatigue in the days after elite rugby league match-play has been well documented, the specific match actions which contribute to fatigue are not well understood. Thus, the purpose of this study was to examine the relationship between the physical demands of elite rugby league match-play and fatigue in the days after. Twenty-eight individual performances from an English Super League team were captured using a 10 Hz global positioning system (GPS). Upper and lower body neuromuscular fatigue, plasma creatine kinase (CK) and perceptual well-being were assessed 24 h before, immediately after, and at 12, 36 and 60 h after a competitive match. Backs covered more distance during sprinting (214.5 ± 117.6 m) and highintensity sprinting (129.6 ± 110.9 m) than forwards (142.9 ± 86.2 and 57.1 ± 67.6 m, respectively), whereas forwards experienced significantly more collisions than backs (75.1 ± 64.1 cf. 37.6 ± 18.8). CK concentration peaked at 12 h and remained significantly elevated up to 60 h post-match (p < 0.05). Large decrements in countermovement jump (CMJ) and small to moderate decrements in repeated plyometric push-up (RPP) performance were evident at 12 and 36 h post-match. Well-being questionnaire (WQ) score was significantly decreased up to 36 h post-match (p < 0.05), specifically large increases in perceived muscle soreness were found at 12 and 36 h. Duration (r = 0.8), total distance covered (r = 0.79) and efforts performed over 18 km·h-1 (r = 0.78) were strongly associated with CK concentration. High intensity accelerations (r = 0.47) and decelerations (r = 0.45) were significantly associated with CK concentration. Total collisions and repeated high-intensity effort (RHIE) bouts were associated with decrements in RPP (r = -0.49 and r = -0.51, respectively), CK concentration (r = 0.56 and r = 0.63, respectively) and perceived muscle soreness (r = -0.52 and r = -0.48, respectively). The findings suggest duration of match-play, high intensity running and collisions experienced were the strongest predictors of fatigue following elite rugby league match-play.