Aerobic performance of young football players in the preparatory period

A contemporary approach to sport training requires a constant inflow of information on the size and rate of adaptive changes taking place in the body of the training footballer. Most studies of this type relate to a small group of professional players. The above problem has been little explored and documented in the case of young players. The aim of this study was to perform a comprehensive assessment of changes in selected indicators characterising aerobic performance in footballers in the preparatory period. The study included a group of 22 junior players from the WKP Lech Poznan football club before and after the basic preparatory period of the 2006/2007 season. In the assessment of aerobic performance the following exercise tests were used: PWC sub(170), the progressive running test to exhaustion - the aim of which is to determine the anaerobic threshold (AT) and establish the threshold running speed, and the Multistage Shuttle Run Test (MST) - a shuttle endurance test which allows to predict the maximum oxygen intake (VO sub(2max)). For the analysis of training loads the method developed in the Department of Theory of Sport of the University of Physical Education in Warsaw was used. The significance of differences between two dates of measurements was established on the basis of Wilcoxon's test. The analysis of the results indicates a clear increase in aerobic exercise capabilities of the studied players after the preparatory period. In relation to all physiological indicators, generally statistically significant changes at p less than or equal to 0.001 were found. Advantageous adaptive changes in terms of the studied physiological indicators may indicate an effective application of individual training loads and good preparation of the team to the spring starting period in terms of aerobic performance. It seems that individualised (at the level of anaerobic threshold) various forms of continuous and changeable running and appropriately selected - in terms of volume and intensity of effort - auxiliary games at various stages of the preparatory period had the greatest influence on the improvement of effort tolerance.