Physiological response to systematic training in adolescent footballers

Abstract

The studies presented in this thesis examined the physiological impact of a systematic training programme on adolescent footballers. The main variables of interest in each study were maturation, training session time and baseline fitness. The current thesis comprises of four studies. Study 1 analysed the birth date distribution of the players in the Performance School programme compared to the general population, as well as how physical prowess was effected by the distribution of birth dates. The results indicated that the Relative Age Effect (RAE) was present within the Performance School programme and an overrepresentation of players born earlier in the selection year was found in every year group. Despite the presence of the RAE, there were no differences found with regards to physical performance between players born at the start or end of the selection year. Study 2 extended the findings in Study 1. Study 2 aimed to examine the contribution of certain variables; training session time, progression in maturity offset and baseline fitness, to change in physical performance over one competitive season. The results in Study 2 indicated that baseline fitness was the largest contributing variable to change in physical performance over time from baseline. Study 3 examined the stability of ranking players based on physical performance in a 20m sprint, change of direction test (COD), SJ assessment and the Yo-yo intermittent recovery test level 1 (YYIRTL1). The study also aimed to assess response to training on an individual, rather than a group, level. The results in Study 3 indicated that stability in ranking differs depending on age group and on measure of physical performance. With regards to individual response, Study 3 showed that performance in YYIRTL1 was most likely to change, given the training stimulus. 3

Finally, Study 4 aimed to assess the differences in physical performance and rate of change in physical performance between groups of adolescent footballers who train and compete at different levels in Scottish football. The findings in Study 4 indicated that, firstly, the only attribute that was able to discriminate between playing standard was the 20m sprint. Furthermore, the only attribute that was suggestive of a greater training session time was performance in the YYIRTL1. However, despite differences in playing standard and training session time, there were no differences found in rate of progression in any of the physical attributes tested.