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The effects of a nucleotide supplement on salivary IgA and cortisol after moderate endurance exercise
L Mc Naughton1, D J Bentley, P Koeppel
1Department of Sport and Exercise Science, University of Hull, Hull, UK. l.mcnaughton@hull.ac.uk
Aim:
The aim of this work was to determine the ergogenic effects of a nucleotide supplement on salivary immunoglobulin A (SIgA) and cortisol (C) responses after prolonged endurance cycle exercise.
Methods:
Fourteen moderately trained male subjects (mean body mass and VO2max) completed 2 90-min cycle ergometer trials (60% VO2max) prior to and after 60 days of either a nucleotide (E group, n=7) or placebo (P group, n=7) supplement. Each of the subjects provided an unstimulated saliva sample prior to and following the exercise for determination of SIgA and C.
Results:
SIgA was significantly lower after exercise trials in both E and P groups (P<0.0001) prior to as well as after the supplementation period. However, SIgA was significantly higher (P<0.01) in the E group than the P group after supplementation. There were no significant (P>0.11) differences in pre-exercise C level. Postexercise C concentrations were significantly (P<0.001) higher than pre-exercise levels in both groups of subjects. However, after the supplementation period, C concentration was significantly (P<0.0001) lower after exercise in E compared to P.
Conclusions:
This work suggests that a nucleotide supplement, given chronically may offset the hormonal response associated with demanding endurance exercise.
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