Mucosal immune responses during court training in elite tetraplegic athletes

Study design: Experimental study. Objectives: To examine salivary secretory immunoglobulin A (sIgA) responses and a-amylase activity during court training in highly trained tetraplegic athletes. Setting: Loughborough, UK. Methods: Seven highly trained wheelchair rugby athletes with tetraplegia performed two separate wheelchair rugby court training sessions, lasting 23 and 41.5min, respectively, with either an aerobic or an interval focus. Timed, unstimulated saliva samples were obtained pre, post and 30min post exercise and analysed for sIgA and a-amylase. Furthermore, blood lactate concentration and rating of perceived exertion (RPE) immediately after training were measured. Results: sIgA secretion rate and a-amylase were unaffected by exercise during both sessions. However, the increases of sIgA concentration (30 min post exercise: þ67±29%) during the aerobic session were accompanied by decreases in saliva flow rate ( 35±22%). Athletes’ physiological responses to exercise document the highly strenuous nature of the sessions, with blood lactate concentrations reaching 8.1±1.0 and 8.7±1.6mmol l 1 and RPE reaching 18(17,18) and 16(15,17) for the aerobic and the interval session, respectively. Conclusion: Acute bouts of highly strenuous exercise do not have negative impacts on the mucosal immune response in tetraplegic athletes, nor do they influence the production of a-amylase, a marker of sympathetic nervous activity. This contrasts responses previously observed in able-bodied athletes. The disruption of the sympathetic nervous system may prevent the downregulation of sIgA secretion rate following intense exercise, which is a response previously observed in able-bodied athletes.