170 Pediatric Exercise Science, 2012, 24, 170-186 © 2012 Human Kinetics, Inc. Rumpf and Cronin are with the Sport Performance Institute New Zealand, University of Technology, Auckland, New Zealand. Pinder is with the School of Engineering, AUT University, Auckland, New Zealand. Oliver and Hughes are with the Cardiff School of Sport, University of Wales Institute, Cardiff, Wales. Effect of Different Training Methods on Running Sprint Times in Male Youth Michael C. Rumpf and John B. Cronin University of Technology Shane D. Pinder AUT University Jon Oliver and Michael Hughes University of Wales Institute The primary purpose of this paper was to provide insight into the effect of differ- ent training methods on sprinting time in male youth aged 8–18 years. Specifc and nonspecifc training methods were identifed, the participants of the fveteen studies chategorized into pre, mid- and postpeak height velocity and effect sizes and percent changes calculated for each training method were appropriate. Plyo- metric training had the most effect on sprint times in pre- and midpeak height velocity participants, while combined training methods were the most effcient in postpeak height velocity participants. However, it is diffcult to quantify the effects of different training methods due to the limited knowledge in this area e.g., resisted training on pre-PHV participants. Furthermore, it may be worthwhile to investigate additional variables (i.e., stride length, stride frequency, horizontal force), to better determine effect of training methods in different maturity statuses, the development of sprinting and possible stages where individual development can be optimized by training. Sprint running is an essential component to many sporting performances. Given this importance, the development of sprint ability is thought critical in athlete development. While Katch (22) claimed no possible training-induced changes in muscular and cardiovascular function after training in prepubertals, more recent literature stated so-called critical periods for training from age 5–9 (8) and 12–15 (7,46) for speed training. These periods have been termed “windows of accelerated adaptation to training” or “windows of trainability” (3). Even though the central nervous system undergoes rapid changes in terms of myelination in the frst 2–5