Plyometrics' Trainability in Preadolescent Soccer Athletes

Abstract

Plyometric training (PT) is a widely used method to improve muscle ability to generate explosive power. This study aimed to determine whether preadolescent boys exhibit plyometric trainability or not. Forty-five children were randomly assigned to either a control (CG, N = 21, 10.6 ± 0.5 years; participated only in regular soccer practice) or a plyometric training group (PTG, N = 24, 10.6 ± 0.6 years; participated in regular soccer practice plus a plyometric exercise protocol). Both groups trained for 12 weeks during the in-season period. The PT exercises (forward hopping, lateral hopping, shuffles, skipping, ladder drills, skipping, box jumps, low-intensity depth jumps) were performed twice a week. Preadolescence was verified by measuring Tanner stages, bone age, and serum testosterone. Speed (0-10, 10-20, 20-30 m), leg muscle power (static jumping, countermovement jumping, depth jumping [DJ], standing long jump [SLJ], multiple 5-bound hopping [MB5]), leg strength (10 repetition maximum), anaerobic power (Wingate testing), and soccer-specific performance (agility, kicking distance) were measured at baseline, midtraining, and posttraining. The CG caused only a modest (1.2-1.8%) increase in speed posttraining. The PTG induced a marked (p < 0.05) improvement in all speed tests (1.9-3.1% at midtraining and 3-5% at posttraining) and vertical jump tests (10-18.5% at midtraining and 16-23% at posttraining), SLJ (2.6% at midtraining and 4.2% at posttraining), MB5 (14.6% at midtraining and 23% at posttraining), leg strength (15% at midtraining and 28% at posttraining), agility (5% at midtraining and 23% at posttraining), and kicking distance (13.6% at midtraining and 22.5% at posttraining). Anaerobic power remained unaffected in both groups. These data indicate that (a) prepubertal boys exhibit considerable plyometric trainability, and (b) when soccer practice is supplemented with a PT protocol, it leads to greater performance gains.

Six weeks of knee extensor isometric training improves soccer related skills in female soccer players

“…Prior research reports increases in KD of 11.5% after 7-weeks of plyometric training in female adolescent players 13 and 22.5% after 12-weeks of plyometric training in pre-adolescent boys. 24 Whilst such rapid increases could potentially be due to age and maturation, Haldankar et al 27 reported 12-weeks of RT significantly improved KD in adult amateur soccer players (11.5%). Increased strength likely contributes to an explosive knee extension motion increasing force production during the final kicking phase.…”

“…22,23 The lack of changes in the present study might also be a result of the short intervention duration. For example, Michailidis et al 24 found that only after 12-weeks of plyometric training did 30m-sprint time reduce by 3%. However, it is thought very specific training is required to optimize COD speed.…”

Agility training in football players: a systematic review

“…El entrenamiento de pesas y el entrenamiento pliométrico pueden provocar adaptaciones estructurales y neurales, las cuales han demostrado ser efectivas para mejorar gestos explosivos (Perez-Gomez & Calbet, 2013); este hecho podría justificar que tanto la utilización de pesas (Christou et al, 2006;Cressey et al, 2007;Jones et al, 2010;Oberacker et al, 2012), como la pliometría (Meylan & Malatesta, 2009;Michailidis et al, 2013;Sohnlein et al, 2014;Vaczi et al, 2013), sirvan como métodos de entrenamiento para provocar mejoras en la agilidad de los futbolistas. La combinación del entrenamiento de fuerza, bajo alguna de las dos modalidades indicadas anteriormente, y de resistencia (McGawley & Andersson, 2013) también ayudan a mejorar el rendimiento en agilidad.…”

“…Se ha observado que entrenar con ejercicios pliomé-tricos, durante un periodo de entre 6 y 16 semanas, permite mejorar la agilidad (Meylan & Malatesta, 2009;Michailidis et al, 2013;Sohnlein, Muller, & Stoggl, 2014;Vaczi, Tollar, Meszler, Juhasz, & Karsai, 2013).…”

“…En otro estudio, añadir al entrenamiento de fútbol, 8 semanas de entrenamiento pliométrico, 2 veces por semana, también mejoraron la agilidad, 10 m esprint con 4 giros de 60º alrededor de una pica, en un 9.6% en niños futbolistas con una edad media de 13.3 años de edad (Meylan & Malatesta, 2009). Utilizando ese mismo test de agilidad, 10 m esprint con 4 giros de 60º, la mejora fue de un 22.6% en niños futbolistas con una edad media de 10.6 años, tras añadir al entrenamiento de fútbol un entrenamiento pliométrico de 12 semanas de duración, entrenando 2 veces por semana (Michailidis et al, 2013). En otro estudio, la práctica de fútbol no fue suficiente para mejorar la agilidad de futbolistas con una edad media de 12.3 años, mientras que el grupo, con una edad media de 13 años, que sustituyó dos sesiones de entrenamiento en fútbol por entrenamiento pliométrico, durante 16 semanas, consiguieron mejorar la agilidad, Hurdle agility run, en un 6.1% (Sohnlein et al, 2014).…”