Purpose: To monitor resting salivary secretory immunoglobulin A (SIgA) levels in international soccer players during the short-term training period that precedes international match play.
Methods: In a repeated measure design, saliva samples were obtained from thirteen outfield soccer players who participated in the training camps preceding 7 games (5 home and 2 away) of the 2014 FIFA World Cup qualifying campaign. Samples were obtained daily for four days preceding each game (and analyzed for SIgA using the IPRO Oral Fluid Collection System) at match day (MD) minus 1 (MD-1), minus 2 (MD-2), minus 3 (MD-3) and minus 4 (MD-4).
Results: SIgA displayed a progressive decline (P = 0.01) during the 4-day training period (MD-4: 365 ± 127 μg.mL-1; MD-3: 348 ± 154 μg.mL-1; MD-2: 290 ± 138 μg.mL-1; MD-1: 256 ± 90 μg.mL-1) such that MD-1 values were significantly lower (P = 0.01) than both MD-4 and MD-3. Ninety-five % confidence intervals for the differences between MD-1 and MD-4 (95% CI = -191 to - 26) and MD-1 and MD-3 (95% CI = -155 to - 28).
Conclusions: Data demonstrate that a short-term soccer training camp in preparation for international competition induces detectable perturbations to mucosal immunity. Future studies should monitor SIgA (as a practical and non-invasive measurement of immunity) alongside internal and external measures of training load in an attempt to strategically individualize training and nutritional strategies that may support optimal preparation for high-level competition.
IJSPP Link: http://journals.humankinetics.com/ijspp-in-press/ijspp-in-press/pre-match-salivary-iga-in-soccer-players-from-the-2014-world-cup-qualifying-campaign