The effectiveness of resistance, plyometric and sprint training at different stages of maturation in male youth athletes

The trainability of youth at specific periods during growth and maturation has become a key issue in paediatric exercise science. The development of physical capacities such as movement speed, strength and power is difficult to predict in youth meaning that the structuring of training can be a significant challenge for coaches. Accordingly, methodologically sound research is required to underpin a more informed approach to the formulation of programmes of physical development. To this end, the purpose of this work was to investigate the trainability of youth athletes at specific stages during maturation (pre-, mid-, and post-peak height velocity) by addressing some of the shortcomings of the existing body of literature. Short-term controlled interventions were undertaken and they extended from the findings of three meta-analytical reviews, all of which examined the effect of training on the development of speed, strength and power in youths aged 9 to 18. These investigations were focused on the manipulation of modifiable factors, such as the training stimulus, as opposed to non-modifiable factors, such as maturity (which was generally controlled for). With some exceptions, which are potentially explainable, speed, strength and power were, on the whole, more trainable in youths as they advanced in maturation with the mid-peak height velocity phase being a particularly important time for the development of these capacities. This could indicate the presence of a maturational threshold which moderates responses to training but this can also be coincident with a period of impaired performance potentially related to reduced motor control due to rapid growth rates. Because of the way speed, strength and power can develop in youth athletes, the pre-peak height velocity phase of development may be more conducive to neuromuscular training with a coordinative component which establishes the movement competency required for more advanced techniques. An intensification of resistance (strength) training can be of benefit during mid-peak height velocity though impaired movement or a higher susceptibility to injury could compel coaches to reduce sprint (speed) and/or plyometric (power) training at this time. During the post-peak height velocity phase, athletes can be transitioned to more advanced training techniques, that are traditionally used with adults, if they possess the necessary coordination and experience to do so. Regardless of the results in this work, at every stage of development it is important for coaches to make programming decisions for youth athletes based, primarily, on training age and movement competency with the above maturity-related recommendations being suitable for those who have been exposed to high quality training from an early age