A recent report in the European Journal of Nutrition suggests that coenzyme Q10 (CoQ10), available as a nutritional supplement, may help athletes recover more quickly from exercise induced oxidative stress and muscle damage. The headlines are certainly exciting: In a group of 20 ultra-endurance athletes markers for oxidative stress and inflammation were reduced among those who took 5 x 30mg of CoQ10 in the two days prior to and immediately before a 50K race at altitude, compared with the placebo group. Additionally creatinine, a marker of muscle damage, was also lower in the CoQ10 group (Diaz-Castro et al., 2011). Conclusion? CoQ10 must be good for speeding up recovery from endurance exercise.
However, previous research with CoQ10 looking at both oxidative stress and performance outcomes have shown no benefit. For example, in a study of 10 male trained cyclists, supplementation with either CoQ10 or a placebo resulted in no difference between the groups in either a ride to exhaustion test, or in blood markers for oxidative stress after an eight-week supplementation and training regime (Braun, Clarkson, Freedson, & Kohl, 1991). Similarly, six weeks of supplementation with 120mg per day in a group of 11 male marathon runners and triathletes resulted in no difference in markers for oxidative stress and performance actually got worse in the CoQ10 group (Laaksonen, Fogelholm, Himberg, Laakso, & Salorinne, 1995). In a double-blind, placebo controlled trial with 37 marathon runners, 90mg of CoQ10 and 13.5mg of vitamin E failed to inhibit muscle damage or oxidative stress any more than the placebo following a marathon race (Kaikkonen et al., 1998). In fact, it is difficult to find any other studies that support the hypothesis that CoQ10 prevents muscle damage in chronic exercise.
So what about these latest findings? Well, one explanation might be that endurance training appears to increase the body’s own antioxidant enzyme systems such as superoxide dismutase (SOD), glutathione peroxidase and catalase. In human subjects a correlation between VO2max and cellular antioxidant capacity has been established, with both catalase and SOD significantly elevated in athletes with a VO2max in excess of 60mL/Kg/min compared to moderately trained individuals (Jenkins, Friedland, & Howald, 1984). Changes in antioxidant enzyme status have even been reported after a single bout of exercise in healthy but untrained adults (mean VO2max 44 mL/Kg/min) with total antioxidant capacity increased by around 8% compared to baseline immediately following exercise on a cycle ergometer (Berzosa et al., 2011). So it is possible that the athletes in this latest study were not elite. Fit, yes, but not elite. Their exact VO2max is not specified, but their average age was 41.25 ± 2.84 years in the CoQ10 group and 39.75 ± 2.92 years in the placebo group, suggesting sub-elite status. Additionally, CoQ10 levels tend to decline with age, so perhaps this group were more likely to see effects from CoQ10 supplementation than a group of younger elites?
What the literature does seem to suggest is the better trained the athlete, the better their antioxidant capacity, and the less prone they are to inflammation and oxidative stress in spite of high training loads. Therefore CoQ10 and other antioxidant supplements may offer some benefits to less well-trained athletes, as long as you don’t subscribe to the theory that oxidative stress is necessary for training adaptations to take place – but that’s another story! As with all these things, the reality is somewhat more complex than the headlines would suggest, and the more you delve, the more confusing it can get. More research is required to validate these latest findings, and suffice to say, there’s absolutely no substitute for good training and good eating, and whilst supplements do have their place, the fundamentals have to be in place first.
References
Berzosa, C., Cebrian, I., Fuentes-Broto, L., Gomez-Trullen, E., Piedrafita, E., Martinez-Ballarin, E., . . . Garcia, J. J. (2011). Acute exercise increases plasma total antioxidant status and antioxidant enzyme activities in untrained men. J Biomed Biotechnol, 2011, 540458. doi: 10.1155/2011/540458
Braun, B., Clarkson, P. M., Freedson, P. S., & Kohl, R. L. (1991). Effects of coenzyme Q10 supplementation on exercise performance, VO2max, and lipid peroxidation in trained cyclists. Int J Sport Nutr, 1(4), 353-365.
Diaz-Castro, J., Guisado, R., Kajarabille, N., Garcia, C., Guisado, I. M., de Teresa, C., & Ochoa, J. J. (2011). Coenzyme Q(10) supplementation ameliorates inflammatory signaling and oxidative stress associated with strenuous exercise. Eur J Nutr. doi: 10.1007/s00394-011-0257-5
Jenkins, R. R., Friedland, R., & Howald, H. (1984). The relationship of oxygen uptake to superoxide dismutase and catalase activity in human skeletal muscle. Int J Sports Med, 5(1), 11-14. doi: 10.1055/s-2008-1025872
Kaikkonen, J., Kosonen, L., Nyyssonen, K., Porkkala-Sarataho, E., Salonen, R., Korpela, H., & Salonen, J. T. (1998). Effect of combined coenzyme Q10 and d-alpha-tocopheryl acetate supplementation on exercise-induced lipid peroxidation and muscular damage: a placebo-controlled double-blind study in marathon runners. Free Radic Res, 29(1), 85-92.
Laaksonen, R., Fogelholm, M., Himberg, J. J., Laakso, J., & Salorinne, Y. (1995). Ubiquinone supplementation and exercise capacity in trained young and older men. Eur J Appl Physiol Occup Physiol, 72(1-2), 95-100.
