Monitoring physiological responses to training and match play in adolescent footballers

Abstract

Introduction: Recently, there has been a growing interest into the monitoring of training and match load and subsequent physiological responses adolescent footballers experience (Malone, 2014). Before a physical performance test can used as a monitoring tool, its reliability must be quantified (Thorpe et al., 2015). Therefore, the aims of this thesis are two-fold: 1) quantify the reliability of a number of physical performance tests and 2) using the same physical performance tests quantify physiological responses to load over acute and chronic training periods. Methodogly: First the reliability of eccentric hamstring strength, isometric adductor strength and linear sprint tests were quantified, in a cohort of adolescent footballers (n = 37). Secondly training and match load was recorded over a 4-week period in another group of adolescent footballers (n = 10). Measures of lower body strength and speed were recorded prior to the start of every training session and match. Results: Acceptable levels of reliability were found for at least one metric of the three physical performance tests. An increase greater than the typical error of the test in eccentric hamstring strength was found after a 4-week training period but despite variations in load, no changes in lower body strength and speed were recorded between training sessions and matches. Discussion: Eccentric hamstring strength, long lever isometric adductor strength and 30-metre sprint performance are reliable tests to assess adolescent footballers. However, these measures are not be sensitive enough to detect true changes in performance in relation to variations in training and match load. Alternative methods must be established that quantify the physiological responses to load experienced by adolescent footballers