Seasonal Analysis of Mucosal Immunological Function and Physical Demands in Professional Australian Rules Footballers

To assess match-to-match variations in salivary immunoglobulin A concentration ([s-IgA]) measured at 36 h postmatch throughout an Australian Football League (AFL) premiership season and to assess the trends between 36-h-postmatch [s-IgA] and match-play exercise workloads throughout the same season. Methods: Eighteen elite male AFL athletes (24 +/- 4.2 y, 187.0 +/- 7.1 cm, 87.0 +/- 7.6 kg) were monitored on a weekly basis to determine total match-play exercise workloads and 36-h-postmatch [s-IgA] throughout 16 consecutive matches in an AFL premiership season. Global positioning systems (GPS) with integrated triaxial accelerometers were used to measure exercise workloads (PlayerLoad) during each AFL match. A linear mixed-model analyses was conducted for time-dependent changes in [s-IgA] and player load. Results: A significant main effect was found for longitudinal postmatch [s-IgA] data (F-16,(240) = 3.78, P < .01) and PlayerLoad data (F16,66 = 1.98, P = .03). For all matches after and including match 7, a substantial suppression trend in [s-IgA] 36-h-postmatch values was found compared with preseason baseline [s-IgA]. Conclusion: The current study provides novel data regarding longitudinal trends in 36-h-postmatch [s-IgA] for AFL athletes. Results demonstrate that weekly in-season AFL match-play exercise workloads may result in delayed mucosal immunological recovery beyond 36 h postmatch. The inclusion of individual athlete-monitoring strategies of [s-IgA] may be advantageous in the detection of compromised postmatch mucosal immunological function for AFL athletes.