Exercise Physiology Research: Mitoquinol and Oxygen Uptake Kinetics in Trained Cyclists
Written by Tyla Cornish (BNatMed), Naturopath. Reviewed by Dr. Siobhan Mitchell (PhD), Neuroscience.
Efficient oxygen utilisation is a key determinant of endurance performance, particularly during transitions in exercise intensity. Mitochondrial function and oxidative stress influence how quickly oxygen uptake kinetics adapt to these changes, making them relevant targets in performance physiology. This study investigated whether short-term mitochondrial antioxidant supplementation could improve oxygen utilisation dynamics and reduce oxidative stress in trained cyclists.
Research Summary
Evidence type: Randomised, controlled intervention
Claim strength: Causal (short-term), mechanistic-positive
Population: 32 healthy trained cyclists
Intervention: Mitoquinol 20 mg/day; exercise training; combined Mitoquinol + training (2 week period)
Primary outcomes: Oxygen uptake kinetics, oxidative stress, antioxidant enzymes, miRNAs
Observed outcome: Faster oxygen uptake kinetics during moderate exercise; reduced oxidative stress; modulation of miRNAs related to vascular inflammation; no standalone performance endpoint improvement beyond kinetics
Causality: Supported for physiological and molecular endpoints
Primary source: FASEB Journal (conference abstract)
What you’ll learn
Whether mitochondrial-targeted antioxidants can improve oxygen uptake kinetics in trained athletes
How exercise efficiency can improve independently of maximal performance measures like VO₂max
The role of oxidative stress in regulating oxygen utilisation during exercise transitions
Why short-term physiological adaptations may not immediately translate into performance outcomes
Why Oxygen Kinetics Were Targeted
Oxygen uptake kinetics reflect how quickly the body adapts oxygen delivery and utilisation to changes in exercise intensity. Slower kinetics can limit performance efficiency by delaying the aerobic contribution during intensity transitions, increasing reliance on anaerobic pathways. Oxidative stress may impair these processes by affecting mitochondrial function and vascular signalling, creating a mechanistic rationale for mitochondria-targeted intervention.
What the Study Observed
Participants were assigned to placebo, exercise, Mitoquinol, or a combined intervention for two weeks. The study found faster oxygen uptake kinetics with combined Mitoquinol and exercise training, reduced reactive oxygen species with Mitoquinol, and altered expression of microRNAs involved in vascular inflammation. These findings suggest improved efficiency of oxygen utilisation during moderate-intensity exercise, mediated at least in part through reductions in mitochondrial oxidative stress and modulation of vascular signalling pathways.
What Are the Implications for Performance and Training?
This study highlights that performance-relevant improvements may occur at the level of efficiency and kinetics before they become apparent in maximal performance indices. Short-term mitochondrial interventions may influence submaximal exercise physiology in ways that are functionally meaningful even when VO₂max remains unchanged, and molecular signalling changes may underpin early adaptations before measurable performance gains emerge in longer trials.
These findings suggest that mitochondrial-targeted supplementation may be most relevant in performance scenarios characterised by repeated changes in intensity, such as interval training, racing surges, or tactical cycling. Improvements in oxygen uptake kinetics may reduce reliance on anaerobic metabolism during these transitions, potentially lowering accumulated fatigue over time. This positions mitochondrial support not as a strategy for increasing maximal capacity, but for enhancing efficiency, recovery between efforts, and the sustainability of repeated high-intensity work.
What Should Practitioners Know About Dosing and Use?
Participants took 20 mg daily for two weeks. Short-term supplementation influenced oxygen utilisation dynamics and reduced oxidative stress, without producing broad performance improvements within the study timeframe. The kinetic findings may be of particular interest in athletes whose performance is constrained by the efficiency of aerobic transitions rather than maximal aerobic capacity alone.
Read the full paper:Mitoquinol supplementation improves oxygen uptake kinetic by reduced reactive oxygen species levels and altered expression of miR-155 and miR-181b
DOI: doi.org/10.1096/fasebj.2022.36.S1.R6226
