The Effects of N-acetylcysteine on Performance and Redox Homeostasis
Status:
Completed
Trial end date:
2016-09-12
Target enrollment:
Participant gender:
Summary
The main objective of the present study was to investigate whether N-acetylcysteine
supplementation in individuals with low glutathione levels would confer ergogenic effects by
replenishing glutathione levels and by reducing oxidative stress. Towards this aim,
investigators sought to exploit the large inter-individual variability in redox biomarker
levels. More specifically, investigators screened 100 male participants for glutathione
baseline levels in blood and formed three stratified groups according to this value (i.e.,
low, moderate and high; 12 individuals per group). After by-passing the regression to the
mean artefact by performing a second glutathione measurement in the three aforementioned
groups, investigators assessed both aerobic and anaerobic physical performance in order to
acquire a more comprehensive view about the ergogenic effectiveness of the antioxidant
treatment. This was accomplished by implementing three different whole-body physical
performance tests (i.e., VO2max test, time trial and Wingate), as opposed to most in vivo
studies that either applied isolated body-part exercise tests (e.g., by isokinetic
dynamometry) or performed a single exercise test (e.g., time-to-fatigue test). It was
hypothesised, that data of the present investigation will bridge the chasm between the
scientific (i.e., chronic antioxidant supplementation blunts exercise performance and
adaptations) and the community-based (i.e., free radicals should anyway be counteracted by
"protective" exogenous antioxidants) truths about the role of antioxidants as ergogenic aids.
It was also hypothesised that the results will show that low glutathione levels are linked to
decreased aerobic and anaerobic physical performance accompanied by increased levels of
oxidative stress and that N-acetylcysteine supplementation will restore both performance and
redox homeostasis. Based on the findings of the present investigation, the widespread routine
practice of consuming antioxidants during exercise training could be changed and the
consumption of antioxidants would be restricted only for those who are deficient in
glutathione.
Phase:
Phase 2
Details
Lead Sponsor:
Aristotle University Of Thessaloniki
Collaborators:
European University Cyprus National and Kapodistrian University of Athens