ABSTRACT
The purpose of this study was to investigate the relation between alterations of salivary secretory immunoglobulin A (SIgA) and the occurrence of upper respiratory tract infections (URTI) in rugby football players.We examined the relationship between the onset of URTI and the daily alterations of SIgA levels in 32 male collegiate rugby football players (20.5±1.3 years) during summer training camp for 36 days.Total of 6 in 32 subjects had the appearance of URTI symptoms (18 %). SIgA secretion rate decreased significantly in the middle of training camp compared to the baseline (P＜0.05). Furthermore, SIgA secretion rate during the appearance of URTI (13.7±1.1μg/min) were significantly lower than that without symptoms (19.2±1.4 μg/min, P＜0.01). These results suggest that serial monitoring of SIgA may be useful to assess the risk status of URTI affection in athletes.