Physiological responses to an intensified period of rugby league competition

J Strength Cond Res. 2013 Mar;27(3):643-54. doi: 10.1519/JSC.0b013e31825bb469.

Abstract

This study investigated the physiological responses to an intensified period of rugby league competition and the subsequent impact on match performance. The participants were 7 rugby league players competing in an international student tournament. The tournament involved three 80-minute games over a 5-day period, with 48 hours between each match. Baseline measures of upper and lower body neuromuscular functions via a plyometric press-up (PP) and countermovement jump (CMJ), respectively (peak power and peak force were measured), blood creatine kinase (CK), and perceptions of well-being were assessed with a questionnaire. These measures were repeated every morning of the competition; neuromuscular fatigue and CK were additionally assessed within 2 hours after the cessation of each game. During each match, player movements were recorded via global positioning system units. There were meaningful reductions in upper (effect size [ES] = -0.55) and lower body (ES = -0.73) neuromuscular functions, and perceptual well-being (ES = -1.56) and increases in blood CK (ES = 2.32) after game 1. These changes increased in magnitude as the competition progressed. There were large reductions in the relative distance covered in high-speed running (ES = -1.49) and maximal accelerations (ES = -0.85) during game 3. Additionally, moderate reductions in the percentage of successful tackles completed were observed during game 3 (ES = -0.59). Collectively, these results demonstrate that during an intensified period of rugby league competition, characterized by only 48 hours between matches, fatigue will accumulate. This cumulative fatigue may compromise high-intensity match activities such as high-speed running, accelerations, and tackling. Furthermore, CMJs and PPs appear to be sensitive measures for monitoring neuromuscular function in rugby league players.

MeSH terms

  • Athletic Performance / physiology
  • Creatine Kinase / blood
  • Fatigue / physiopathology*
  • Football / physiology*
  • Humans
  • Lower Extremity / physiology
  • Male
  • Muscle Fatigue / physiology*
  • Physical Endurance / physiology
  • Physical Exertion / physiology*
  • Upper Extremity / physiology
  • Young Adult

Substances

  • Creatine Kinase