The purpose of this study was to examine the effect of repeated bouts of br
ief, intermittent, maximal effort exercise on the concentration of secretor
y IgA (S-IgA) and incidence of upper respiratory tract infection (URTI) in
females. Twenty-six non-smoking, active, adult females participated in this
study. The exercise intervention consisted of three consecutive, all-out 3
0-second Wingate leg cycling tests (0.075 kg/kg body mass), which were sepa
rated by three minutes of recovery. Unstimulated saliva was collected prior
to (PRE) and five minutes after completion (POST) of the exercise testing
protocol. IgA, protein and osmolality were measured, and secretory IgA (S-I
gA), IgA:Protein, and IgA:Osmolality were calculated. In addition, subjects
completed standard logs indicating signs and symptoms of upper respiratory
tract infection (URTI) for three weeks following the test. Saliva flow rat
es (478.5 +/- 50; 345.4 +/- 50 mul/min), S-IgA (55.8 +/- 4.7; 35.4 +/- 3.6
mug/min), and IgA:Protein ratio (30.7 +/- 3.0; 17.5 +/- 1.8 mug IgA/mg prot
ein) were significantly lower POST compared to PRE (P<0.05). No significant
differences were observed for raw IgA, protein, osmolality, and IgA:osmola
lity. The results of this study show that brief, intermittent, maximal effo
rt exercise results in an acute decrease in S-IgA in healthy adult females
in less than eight minutes. However, this exercise induced transient decrea
se did not appear to be associated with an increase in clinical symptoms of
URTI in the weeks following the exercise test intervention.