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Published on: February 7, 2018
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Antioxidant supplementation, redox deficiencies and exercise performance: A falsification design
Nikos V Margaritelis1, Vassilis Paschalis2, Anastasios A Theodorou3
1Department of Physical Education and Sport Science at Serres, Aristotle University of Thessaloniki, Serres, Greece; Dialysis Unit, 424 General Military Hospital of Thessaloniki, Thessaloniki, Greece.
Free Radical Biology & Medicine
|July 20, 2020
Summary
Personalized antioxidant supplementation, targeting vitamin C or N-acetylcysteine (NAC) deficiencies, improved exercise performance in deficient individuals. Non-targeted supplementation did not yield similar benefits, highlighting the importance of identifying responsive phenotypes.
Area of Science:
- Exercise Physiology
- Nutritional Biochemistry
- Biomarkers of Oxidative Stress
Background:
- Personalized nutrition strategies are emerging.
- Redox balance plays a role in exercise performance.
- Identifying individuals who benefit from antioxidant supplementation is crucial.
Purpose of the Study:
- To validate personalized redox supplementation.
- To investigate targeted vs. non-targeted antioxidant administration.
- To assess the impact on oxidative stress and exercise performance.
Main Methods:
- Seventy-three volunteers screened for plasma vitamin C and erythrocyte glutathione.
- Three groups formed: low vitamin C, low glutathione, and control.
- 30-day crossover design with 1g vitamin C or 1.2g NAC daily, followed by a 30-day washout.
Main Results:
- Both vitamin C and NAC reduced systemic oxidative stress in deficient groups.
- Targeted supplementation (vitamin C for low VitC, NAC for low GSH) improved VO2max and peak torque.
- Performance improvements were specific to the targeted treatment, not seen in control or non-targeted groups.
Conclusions:
- Personalized antioxidant supplementation is effective when addressing specific deficiencies.
- General antioxidant use is not justified solely by the presence of oxidative stress.
- Identifying 'responsive' phenotypes is key for effective antioxidant strategies.
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