INTRODUCTION: The centralisation process in high-performance sport usually involves a nation`s top athletes leaving home-training squads to join better resourced programmes. Although this process has been widely credited for the Olympic medal-winning success of teams such as British Cycling and Rowing New Zealand, the success of centralisation strategies in elite sport has rarely been evaluated objectively. Here we present a method for analysing the performance progression of swimming squads, which we have used to assess the effect of the centralisation of New Zealand`s elite swim programme in 2002. METHODS: All official long-course performance times for New Zealand swimmers between 2002 and 2013 were downloaded from takeyourmarks.com. Best annual times of all swimmers with at least three years of performances in an event (276,000 times from 8226 swimmers) were analysed separately for males and females using a mixed linear model. The model produced estimates of mean annual performance for 176 swim clubs and mean estimates of the deviation of swimmers` performances from their individual quadratic trajectories after they joined the centralised high performance centre (HPC). Effects were evaluated using magnitude-based inferences with a smallest important change in performance time of 0.24%. RESULTS: Before 2009, the effects of HPC membership were mostly unclear and trivial to small in magnitude. Thereafter, both sexes showed clear additional enhancements in performance, increasing from large in 2009 (males 1.4%, ±0.8%; females 1.5%, ±0.8%; mean, ±90% confidence limits) through to extremely large in 2013 (males 6.8%, ±1.8%; females 9.9%, ±2.9%). Some clubs also showed clear trends in performance during the 12-year period. DISCUSSION: Swimming New Zealand`s centralisation strategy took several years to produce substantial performance effects. Possible reasons for the increasing performance benefits for HPC swimmers from 2009 onwards include additional funding, recruitment of top coaches, and improvements in sport-science and medicine provision, all of which began to be introduced into the HPC in late 2006. Our study shows that a mixed modeling method to assess deviations from individual trends in competition performance can be used to evaluate performance-enhancement strategies introduced at club or national level.
© Copyright 2014 19th Annual Congress of the European College of Sport Science (ECSS), Amsterdam, 2. - 5. July 2014. Veröffentlicht von VU University Amsterdam. Alle Rechte vorbehalten.