Test-retest reliability of physiological and performance responses to 120 minutes of simulated soccer match-play

Objectives: The reliability of the Soccer Match Simulation (SMS) and the physiological and performance responses to 120 minutes (90 plus an additional 30 min period; extra-time) of soccer-specific exercise were investigated.

Design: Test-retest

Methods: Ten university-standard soccer players completed the SMS on two occasions under identical conditions. Capillary and venous blood samples were taken pre-exercise, half-time, at 90 min and at 120 min and further capillary samples were taken every 15 min during exercise. Core temperature (Tc) as well as physical (20 m sprint speeds, countermovement jump height, 15 m sprint velocities) and technical (soccer dribbling) performance was assessed throughout each trial.

Results: There was no systematic bias between trials in all variables except blood lactate. CVs and Pearson’s r during the last 15 min of extra-time were: Tc: 1.2%, 0.9; 20 m sprint speed: 3.5%, 0.7; jump height: 4.9%, 0.9; 15 m sprint velocities: 4.6%, 0.3; dribble velocity: 2.8%; 0.9; dribble precision: 11.5%, 0.3; blood glucose and lactate: 7.1%, 0.9 and 18.6%, 0.7; plasma insulin: 10.3%, 0.9, creatine kinase: 28.1%, 0.4, interleukin-6: 24%, 0.9; non-esterified fatty acids (NEFA): 13.2%, 0.7; glycerol: 12.5%, 0.9. Blood glucose and lactate and sprint and jump performances were reduced and Tc, NEFA, glycerol and creatine kinase concentrations were elevated in the last 15 min of ET (p < 0.05).

Conclusions: The SMS is a reliable protocol for measuring responses to 120 min of soccer-specific exercise. Extra-time compromises both performance and physiological responses.