INTRODUCTION: Physical and psychological load of small-sided games (SSGs) can affect players` neuromuscular and cognitive performance [1,2]. The question remains which of load variables are responsible for the impairment of performance in youth soccer players. This study investigates players` neuromuscular and perceptual-cognitive performance i) response to SSG, ii) relationship with external load and perception of fatigue. METHODS: Sixteen academy soccer players (13.6±0.5y, 163.4±5.9cm, 50.4±7.1kg) underwent SSG 4v4 + GK (40x25m) consisting of six 4-min intervals separated by 1-min recovery. Exercise intensity was monitored by the tracking system Polar Team Pro (Polar, Kempele, Finland). Before and after SSG a 100-mm visual analog scale (VAS-F) determined subjective perception of fatigue, followed by planned (PA) and reactive (RA) agility tests, countermovement jump (CMJ), divided attention task (DA), and go/no-go task (GNG). Paired t-test and Wilcoxon signed-rank test were used to analyze performance changes. Individual pre-post differences (*) were aligned with load variables to calculate Pearson`s (r) or Spearman`s (rs) correlation coefficients. RESULTS: Players achieved 87±4% HRmax with a relative distance covered of 92±7 m/min. Subjective perception of fatigue increased after SSG (41.56±14.02%, p=.001). Further, CMJ height decreased (-6.67±6.64%, p=.014, d=.56), whilst PA time (3.71±2.50%, p=.002, d=.97), RA time (6.60±7.36%, p=.003, d=1.78) and errors in GNG increased (46.43±138.3%, p=.039, d=.59). There were no significant changes in DA task errors (3.66±16.81%, p=.362, d=.22) and speed of response in GNG task (-3.36±8.04%, p=.119, d=.29). Additionally, significant correlation was found between *PA and *VAS-F (r=.60, p=.014), and moderate between *PA and low to medium intensity decelerations (r=.48, p=.061). *RA correlated significantly with *CMJ height (r=-.54, p=.031) and moderately with *GNG errors (rs=.47, p=.123). Sprinting distance (*21 km/h) and maximal speed in SSG correlated with *CMJ height (rs=.66, p=.006; r=.54, p=.032) while high-intensity accelerations correlated with *PA (r=-.76, p=.002). CONCLUSION: Fatigue induced by SSG load affects youth players` agility, explosive strength, and decision-making in visual inhibition task. PA time was associated with fatigue perception and low to medium intensity decelerations. In addition, there was a relationship between explosive strength decrement and RA time. This variable was moderately associated with increased errors in GNG task. However, players who covered a longer sprinting distance and achieved higher maximal speed in SSG had smaller decrement in CMJ height, and those producing a higher number of high-intensity accelerations had smaller increase in PA time. High-intensity actions in SSG may, to some extent compensate for neuromuscular performance decline in young players.
© Copyright 2023 28th Annual Congress of the European College of Sport Science, 4-7 July 2023, Paris, France. Published by European College of Sport Science. All rights reserved.