Selected immunoendocrine and performance adaptations to upper-body plyometric training and β-alanine supplementation in male swimmers

BACKGROUND: Upper-body plyometric training (PT) enhances neuromuscular performance and power production. However, its application in swimming and its potential interaction with β-alanine (BA) supplementation remain largely unexplored. Therefore, this study investigated the combined effects of upper-body PT and BA supplementation on performance and immunoendocrine adaptations in trained male swimmers. METHODS: Assessments conducted before and after the intervention included medicine ball throw (MBT), push-up endurance, one-repetition maximum (1RM) bench press, swim ergometer peak and mean power output (PPO and MPO), and 50-, 100-, and 200-m freestyle performance. Blood samples were also collected pre- and post-intervention to determine testosterone, cortisol, and immunoglobulin A (IgA) concentrations. RESULTS: < 0.05), with effect sizes ranging from small to moderate. CONCLUSIONS: β