Co-Q10 may reduce fatigue after exercise
According to Japanese researchers, coenzyme Q10 supplements may boost physical performanceand reduce feelings of tiredness associated with exercise.
Both fatigue and recovery time were decreased as a result of 300 milligrams of CoQ10 for eightdays, according to the double-blinded, placebo-controlled study with 17 healthy volunteers. Thestudy was published in the journal Nutrition.
According to the lead author, Kei Mizuno, "We found that oral administration of 300 mg ofcoenzyme Q10 for 1 wk improved physical performance during fatigue-inducing workload trialson a bicycle ergometer."
The dose of coq10 seems to be the critical factor. "However, this positive result was not seen inthe group administered 100 mg of coenzyme Q10," said Mizuno.
CoQ10 has properties similar to vitamins, but since it is naturally synthesized in the body it is notclassed as such. With chemical structure2,3-dimethoxy-5-methyl-6-decaprenyl-1,4-benzoquinone, it is also known as ubiquinone becauseof its 'ubiquitous' distribution throughout the human body.
The level of CoQ10 produced by the body begins to drop after the age of about 20, and thecoenzyme is concentrated in the mitochondria - the 'power plants' of the cell. It plays a vital rolein the production of chemical energy by participating in the production of adenosincetriphosphate (ATP), the body's co-called 'energy currency'.
A role beyond the mitochondria is also acknowledged, with CoQ10 acting as a potentantioxidant. The coenzyme plays an important role in preserving levels of vitamin E and vitaminC.
Researchers from Osaka City University Graduate School of Medicine, Soiken Incorporation,Kansai University of Welfare Sciences, and Osaka University of Foreign Study, recruited the 17volunteers (average age 37.5) and randomly assigned them to receive daily coenzyme Q10supplements (100 or 300 mg, Kaneka Corporation) or placebo for eight days. All subjectsunderwent the three interventions, with washout periods separating the eight-day long studies.
Physical performance, tested using a bicycle ergometer at fixed workloads, was found to increasewhen the subjects received the 300 mg CoQ10 dose, compared to the lower dose CoQ10 groupand the placebo group.
Furthermore, subjective fatigue sensation in the high dose CoQ10 group was "alleviated whencompared with that in the placebo group," wrote the researchers.
According to background information in the article, fatigue, which can occur in both healthy andill people, is "best defined as difficulty in initiating or sustaining voluntary activity and can beclassified into mental and physical fatigue."
Commenting on the potential mechanism, the Japanese researchers wrote: "Exercise-inducedreductions in energy substrates, reactive oxygen species, and protein oxidation are thought to beassociated with physical fatigue. Coenzyme Q10 is a vitamin-like, lipid-soluble compoundexisting in all cells. It is an indispensable compound in the respiratory chain of the innermitochondrial membrane and acts as an essential antioxidant assisting in the regeneration ofother antioxidants
"Therefore, administration of coenzyme Q10 may attenuate physical fatigue through its functionsas an antioxidant or in assisting oxidative phosphorylation."
Kaneka is a leading producer of coQ10, manufacturing both ubiquinone and, more recently, thereduced form of coQ10, ubiquinol. It would be interesting to see if a lower dose of ubiquinolwould be as effective at 300 mg of ubiquinone for this purpose.
Reference: Nutrition (Elsevier); Published online ahead of print
13 February 2008, doi:10.1016/j.nut.2007.12.007
"Antifatigue effects of coenzyme Q10 during physical fatigue"
Authors: Kei Mizuno, M. Tanaka, S. Nozaki, H. Mizuma, S. Ataka, T. Tahara, T. Sugino, T.Shirai, Y. Kajimoto, H. Kuratsune, O. Kajimoto, Y. Watanabe