Creatine Monohydrate

Coenzyme Q10 (CoQ10), sometimes referred to as ubiquinone, is a lipid-soluble coenzyme produced by respiring organisms and some photosynthetic bacteria. CoQ10 aids in the transport of electrons between enzyme complexes of the inner mitochondrial membrane. Through the process of oxidation phosphorylation, CoQ10 also aids in the production of ATP.

Human Studies

The effects of CoQ10 supplementation have been studied using patients with chronic obstructive pulmonary disease (COPD). Eight patients ingested 90 mg/day of CoQ10 for 8 weeks and showed a significant increase in serum CoQ10 levels with a decrease in hypoxemia at rest. Tread­mill time tended to increase (12.0-14.0 min) with a significant decrease in heart rate during exercise, whereas lactate production decreased. However, pulmonary function and oxygen consumption during exercise were unaltered.

Studies have also been conducted on elite athletes. Twentyfive Finnish top-level cross-country skiers ingested 90 mg/day of CoQ10 in a double-blind, crossover fashion. Supplementation significantly improved the subjects . Also, 94% of the athletes felt their performance and recovery times were improved during the supplementation period versus only 33% during the placebo period.

Conversely, ten male bicycle racers performed graded cycle ergometry before and after supplementation with 100 mg/day of CoQ10 or a placebo for 8 weeks. There was a significant difference in serum CoQ10 levels between groups. Both groups showed improvements in exercise performance, but there were no significant differences between groups.

Snider et al. supplemented 11 highly trained male triathletes with three daily doses of a combination of 100 mg of CoQ10, 500 mg of cytochrome C, 100 mg of inosine, and 200 IU of vitamin E or a placebo for two, 4-week periods. There was a 4-week washout between treatment periods in this double-blind crossover design study. After each treatment period, the subjects ran on a treadmill at 70% for 90 minutes followed by a period of cycling at 70% until exhaustion. There were no significant differences between groups for time to exhaustion, blood glucose levels, lactate levels, and free fatty acid concentrations.

Eighteen male road cyclists and triathletes were supplemented with 1 mg/kg/day of CoQ10 or a placebo for 28 days The subjects were evaluated during and after graded cycling exercise tests. Plasma CoQ10 levels were significantly increased from baseline. Nonetheless, CoQ10 had no consistently significant effect on oxygen uptake, anaerobic and respiratory compensation thresholds, blood lactate, glucose and triglyceride kinetics, heart rate, or blood pressure during and following the exercise protocol.

In 1996, MaIm et al. conducted research on CoQ10 using healthy males. The results showed that CoQ10 might actually cause cell damage under intense exercise conditions. MaIm et al also conducted a follow-up study on CoQ10. Subjects ingested CoQ10 for 22 days while performing aerobic exercise, except on days through the subjects performed high-intensity anaerobic training. The results showed that during an anaerobic cycling test, the placebo group performed significantly better than the CoQ10 group on day of supplementation (9.7 versus 9.3 W/kg for the placebo and CoQ10 groups, respectively). Furthermore, the CoQ10 group had a significantly lower increase in total work performed. Overall, there were no significant differences between the groups , rate of perceived exertion (RPE), respiratory quotient, blood lactate concentration, or heart rate.

CoQ10 may aid in the transportation of electrons with­in the mitochondria and also aid in the production of ATP However, it probably does not enhance endurance performance.

Safety and Toxicity

Studies have been conducted on the safety and effectiveness of CoQ10 supplementation in patients who suffer from heart failure. These studies showed an improvement in the patient’s health status However, the results from a study using healthy males showed that supplementation with CoQ10 may cause some cell damage in the intramembrane compartment of the mitochondria.