DATA - IMPACT OF SLEEP RESTRICTION AND TRAINING INTENSIFICATION ON MUCOSAL IMMUNITY AND PSYCHOLOGICAL RESPONSES IN YOUNG SOCCER PLAYERS

This study analyzed the effects of training intensification during a period of sleep restriction on mucosal immunity (salivary IgA), upper respiratory tract health, mood states, and stress tolerance in young soccer players. Sixteen male youth soccer players completed seven weeks of training with varied workloads. Weeks 3 and 5 involved a 75% increase in internal training load (ITL), with extended sleep in week 3 and restricted sleep in week 5. ITL was assessed using session-RPE, and sleep was monitored via actigraphy. Salivary IgA was assessed through salivary collection, and upper respiratory tract infection (URTI) severity was evaluated using the Wisconsin Upper Respiratory Symptom Survey (WURSS-21). Recovery, stress tolerance, and mood were measured using the Perceived Recovery Scale, Daily Analysis of Life Demands in Athletes (DALDA), and Brunel Mood Scale (BRUMS), respectively. Salivary IgA concentrations significantly decreased in weeks 3 (β=-87.41, p=0.007) and 5 (β=-114.04, p<0.001). In week 5, URTI severity increased significantly (p=0.001), while recovery status, stress tolerance, and mood worsened (p<0.05). These findings emphasize the negative impact of training intensification and sleep restriction on mucosal immunity, upper respiratory tract health, and well-being, highlighting the importance of adequate sleep during intensified training to maintain physical and psychological health.