An investigation into a self-regulated approach to repeated sprint exercise in elite youth association football players

Abstract

Recent studies have applied an individualised approach to repeated sprint exercise (RSE), whereby participants are given the freedom to self-determine inter-interval recovery periods based on individual perceptions of recovery (Glaister et al, 2010; Phillips et al, 2014). These studies have suggested that such an approach may be a useful alternative to RSE with the aim of maintaining sprint performance. However, these studies have been conducted exclusively on adults, with no research conducted in young athletes. The aim of the present thesis was to evaluate the influence of using self-selected recovery periods with the aim of maintaining sprint time on performance and the physiological responses to repeated sprint exercise (RSE) in elite youth association football players. A second aim of the thesis was to assess the influence of maturation on the ability to self-determine recovery intervals between sprints. Chapter three assessed performance during a 10 x 30 m sprint task with a 30-second standardised recovery (SR) period, using self-selected recovery with no external cue (NEC), and facilitated by the use of a perceived readiness (PR) scale to assist with self-guidance of recovery intervals, whilst also examining differences in performance and recovery duration between more and less mature players. Twenty-eight elite youth association football players (aged 13 ± 0.9 years) were recruited for the study, with participants split into a more mature (aged 14 ± 0.5 years) and less mature group (aged 13 ± 0.9 years) based on stage of growth in relation to peak-height-velocity. The results demonstrated that participants displayed a tendency to underestimate the recovery time required to maintain performance during the NEC and PR trials, resulting in impaired performance when compared with the SR trial, in which recovery intervals were significantly longer and performance was better maintained. Despite exhibiting less fatigue when SR periods were used, less mature participants displayed an impaired ability to guide recovery intervals with NEC, as displayed by the moderately higher sprint decrement compared with the more mature group. Chapter four evaluated the physiological, neuromuscular and perceptual responses to RSE with self-guided (SG) recovery periods compared with a 30-second standardised recovery (SR) period in 11 participants (aged 13 ± 0.9 years). This study suggests that using SG recovery induces a significantly higher physiological and metabolic stress on participants, with significantly higher post-exercise blood lactate values and moderately higher average HR values compared with the SR trial, likely due to the significantly shorter recovery periods used. These studies provide novel insight into the influence of using self-selected recovery periods on performance and the physiological response to RSE in young athletes.