Effects of Congested Matches and Training Schedules on Salivary Markers in Elite Futsal Players

Abstract

A congested match and training schedule could alter internal load, and this could be reflected in biomarkers of stress and immunity in elite futsal players. The aim of this study was to analyze the effects of a congested match and training schedule on internal load and levels of total protein, total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index, and the concentrations of salivary immunoglobulin A (SIgA) in 17 professional players from the same Portuguese elite futsal club (age: 23.07 ± 6.76 years old; height: 1.75 ± 0.06 m; body mass: 75.47 ± 7.47 kg; experience in playing in elite: 5.38 ± 2.03 years) who performed 5 matches and 16 training sessions in a period of 27 days. The salivary content of total protein, TOS, TAC, oxidative stress index, and SIgA were calculated before and after the training sessions and the unofficial matches under study. Saliva sampling was conducted 10 min before each match or training session and 40 min after (post-match and post-training). The MANOVA of repeated measures showed a significant difference for total protein and SIgA (p < 0.01). Total protein (sphericity = 0.007; statistical power = 0.818) and SIgA (sphericity = 0.018; statistical power = 0.693) are highly correlated with the time factor. The main findings revealed several key points: (a) There was a significant increase in total protein, SIgA, and TAC during acute load (pre- vs. post-session) in both training and match contexts. Specifically, total protein and SIgA displayed notable increments in both training and match settings, while TAC exhibited significant increases exclusively during matches. (b) No changes in TOS and oxidative stress index were observed during acute load in either training or match contexts. (c) A positive trend was noted between the chronic load during a congested week of the precompetitive season and the decrease in total protein and SIgA levels. (d) Additionally, a positive correlation between internal training loads and oxidative/antioxidant responses was found, as expressed by the oxidative stress index, without significant differences (p-value > 0.05) in acute and chronic loads during congested matches and training schedules.