The effects of single and repeated bouts of soccer-specific exercise on salivary IgA

Objective: Athletes frequently train with a short time recovery between sessions. The present aim was to establish how salivary IgA is altered following two soccer-specific intermittent exercise bouts performed on the same day. Design: Ten males participated in two experimental trials (single session, double session) 1 week apart, in a counterbalanced design. One trial entailed afternoon exercise only (PMEX), in which participants completed soccer-specific intermittent exercise starting at 14:30 h. On the other occasion, participants performed two bouts of exercise [starting at 10:30 h (AMEX₁) and at 14:30 h (PMEX₂)]. Timed unstimulated saliva samples were collected before and immediately after exercise. Results: Mean salivary IgA levels increased significantly immediately post-exercise in the single afternoon trial (PMEX). Performance of a second soccer-specific exercise bout in 1 day elicited an increase in heart rate and perceived exertion, compared with the single session, but did not appear to suppress salivary IgA outcomes. Performing soccer-specific exercise at these different times of day did not affect the salivary IgA concentration and secretion rate or salivary cortisol in the short term. Conclusions: These findings suggest that, two 90-min exercise sessions performed at a moderate intensity with a 2.25 h rest in between do not necessarily have adverse effects on salivary IgA levels.