Effect of time of day exercise on acute responses of salivary IgA, cortisol, α-amylase and total protein in female swimmer [In Persian]s

چکیده مقاله

Abstract
Aim: To examine whether time of day significantly affects salivary IgA,
cortisol, α-amylase and total protein levels before and after sub-maximal
swimming.
Method: Fourteen female swimmers (age 13±1.33 years, weight 48±4.75
kg, Vo2max 45.92±3.96 ml/kg/min) volunteered to participate in the study.
In a fully randomized, cross over design, each subject performed 10×200 m
front crawl at 80% of their seasonal best time, with one minute rest between
each 200 m, at 08:00 and 18:00 hours on two days aware. Timed,
unstimulated saliva samples were collected before and after exercise. Saliva
samples were analyzed by two-factor analysis of variance (ANOVA) with
repeated measures. Statistical significance was accepted at p<0.05.
Results: Significant time of day effects (am and pm respectively) were
observed in s-IgA, S-IgA, cortisol, and saliva flow rate, αamylase and total
protein before exercise (P<0.05). The exercise protocol did not significantly
affect s-IgA but, in comparison with values before exercise, caused
significant alterations in cortisol, S-IgA, saliva flow rate, αamylase and total
protein (P<0.05). There was no significant interaction effect of time of day
by exercise on any salivary variables measured except αamylase.
Conclusion: These results suggest a significant circadian variation in the
variables measured before exercise, with showing a significant effect on
their acute responses to exercise except s-IgA and a significant interaction
effect of time of day by exercise on salivary αamylase.
Key words: Time of day, Cortisol, IgA, α-amylase, Total protein