Kinematic analysis of intermittent sprints of elite soccer players

Authors evaluated kinematic characteristics of running velocities during intermittent 10 x 30 m sprints. Authors also attempted to determine if there are any significant change in human organism homeostasis after 10x30m intermittent sprints and if the maximal and temporary velocities evaluated continuously are different after consecutive repetitions of maximal sprints. The experiment was conducted on 19 male Polish first division soccer players aged 24,4 ± 3,5 years. The mean body height and mass were equal respectively 178,5±7,9 cm and 76, 5± 5,7 kg. The speed abilities were evaluated with the use of the laser diode system LDM300CSport (Laser Device Measurement from Jenoptik in Jena). The testing protocol included 10×30 m sprints with 20 s recovery periods. According to laser measuring system the data of whole distance were recorded: velocity (1, 5, 10, 15, 20 and 30 m), maximal velocity in each sprint (Vmax) and distance at which maximal velocity SVmax [m] was obtained. Obtained experimental data and theoretical overview allowed to conclude that repeated 30 m sprints with short rest intervals significantly disturbed body homeostasis. The maximal velocity decreases with each sprint reaching lowest level in 10th repetition and the changes of mean velocities at chosen distances in consecutive sprints decreases but the course of changes have an unjustified character