Clinical Research Directory

S-Acetyl Glutathione and Performance Recovery in Soccer

Soccer players display elevated inflammatory and oxidative stress markers combined with reduced soccer specific performance over a 72-hour period. However, in modern soccer, players participate very often in 2 or 3 matches within a week, with a recovery period of 72 hours between successive matches, that is insufficient to restore skeletal muscle homeostasis and performance. Of note, reduced glutathione (GSH) levels, a tripeptide consisting of the amino acids cysteine, glycine and glutamic acid, are substantially reduced during the 72-hour recovery period after a match because of the trauma-related acute inflammatory and oxidative stress response. GSH availability is a crucial regulator of cellular redox status, affecting numerous intracellular and physiological processes such as redox signalling, immunoregulation and muscle metabolism. Indeed, enhanced GSH availability following muscle damaging exercise has been shown to be beneficial for skeletal muscle and performance recovery by mitigating the inflammatory and oxidative stress response. Thus, the enhancement of GSH availability through dietary interventions would be a promising strategy to accelerate skeletal muscle and performance recovery following a soccer game. S-Acetyl Glutathione (SAG) is a glutathione precursor with enhanced absorption kinetics due to chemical S-acetylation of the thiol group on the cysteinyl amino acid of GSH and oral administration of SAG has been shown to be more effective in restoring intracellular glutathione levels compared to oral glutathione. The aim of this study is to (i) perform a pharmacokinetic assessment of 200 mg/day vs 500 mg/day of SAG during a 7-day supplementation period (pre-loading) and (ii) to establish the pharmacodynamic effect of the two dosages at 24, 48 and 72h following a 90-minute official soccer match.

The Effect of a Training Programme in the Variation of Fitness Parameters, Physiological, Hematological and Biochemical Indicators of Soccer Players During the Preseason Period

The goal of this study is to investigate the effects of varying friendly match-play exposure during the late pre-season on physiological, biochemical, and performance adaptations in soccer players. It is hypothesized that (i) significant changes will occur across the pre-season in both the extended- and limited-play groups when analysed independently; (ii) distinct group-specific adaptations will emerge by the end of the preparatory period; and (iii) match-play exposure, when analysed across all participants, will be significantly correlated with physiological and performance outcomes at pre-season completion. Players from a randomly selected team will be assessed at three time points: pre-season start, mid-pre-season (MPS), and pre-competition phase (PC). Assessments will include anthropometry, physical performance, and markers of muscle damage, inflammation, hormonal status, and haematology. Based on the total match-play time of 8 friendly games during the late pre-season, players will be retrospectively categorised into extended-play (EP) and limited-play (LP) cohorts.time of 8 friendly games during the late pre-season, players will be retrospectively categorised into extended-play (EP) and limited-play (LP) cohorts.