What it is:A vitamin-like, fat-soluble compound of the ubiquinone family, coenzyme Q10 functions in all cells of the body, serving as a coenzyme for several of the key enzymatic steps that facilitate ATP production through aerobic respiration within the mitochondrial electron transport chain. Coenzyme Q10 also doubles as potent antioxidant, helping destroy free radicals before they can cause damage to normal cells within the body. Coenzyme Q10 is found naturally in highest concentration within organs and muscles demanding the most energy, such as the heart. Coenzyme Q10 can also be found in such dietary sources as meat, poultry, and fish.
How it works:The human body is on a continuous mission to generate enough energy to support the performance of every cell. It is thought that increased dietary intake of coenzyme Q10, through whole food or supplementation, may help the body keep up the demand for mitochondrial ATP synthesis, especially when demand exceeds production during times of stress, including the stress of physical exertion on the cardiovascular system as well as the stress of muscle recovery from athletic injury. In addition, as a potent antioxidant in both the mitochondria and lipid membranes, coenzyme Q10 helps to combat the 10- to 20-fold increase in molecules called reactive oxygen species (ROS) during physical exercise that can contribute to muscle injury and decreased performance.
Performance benefit:Purported performance-focused benefits of coenzyme Q10 supplementation include improved oxygen usage in the heart and skeletal muscles, leading to increases in maximal aerobic capacity, anaerobic endurance, and overall work capacity. Coenzyme Q10 is also marketed as a recovery agent, helping to reduce exercise-induced muscle injury.
Research:While research has shown intense physical training to lower blood levels of coenzyme Q10, there are mixed results on the validity of daily supplementation to produce enhancements in cardiovascular-focused performance variables. The majority of double-blind and placebo-controlled studies fail to demonstrate any significant enhancement with a daily supplementation protocol of 60-150 mg followed over 4-8 weeks regardless of fitness status (trained vs. untrained) (Zhou et al., 2005; Bloomer et al., 2012; Ostman et al., 2012). Some scientists believe this may be due to inefficient absorption of coenzyme Q10 into the mitochondrial membrane, leaving open the possibility of better results with increased bioavailability (Liao et al., 2007). Nonetheless, while the current consensus remains primarily negative with respect to coenzyme Q10’s impact on cardiovascular performance parameters, the studies evaluating its impact on muscle recovery remain positive. A double-blind study on elite martial arts athletes, for example, discovered that a daily supplementation protocol of 300 mg of coenzyme Q10 for 20 days during a period of intense training significantly lowered levels of the lipid peroxide, a free radical that contributes to oxidative stress in the body, and creatine kinase, an enzyme that signals muscle damage and injury, thereby helping protect against exercise-induced muscle injury and improving recovery (Kon et al., 2008).
Common usage:Per study protocols, recommended doses for adult athletes over 18 years range from 60 to 300 mg/day taken continuously for at least 3 weeks. For doses higher than 100 mg/day, it is best to split the does into 2-3 smaller doses and take them with meals containing some fat to facilitate more efficient absorption. While coenzyme Q10 is available in many forms, soft gels tend to be better absorbed than capsules or other preparations.
Health concerns:Coenzyme Q10 is generally safe, with the exception of infrequent reports of nausea, loss of appetite, upset stomach, and diarrhea. Due to several drug-nutrient interactions, however, athletes taking any form of medication are advised to consult a physician before starting a supplementation protocol.
Additional performance benefits:Athletes with muscle wasting diseases, such as muscular dystrophy, as well as diabetic and master’s level athletes are thought to carry lower levels of coenzyme Q10 and might benefit the most from supplementation.
The Athlete's Guide to Sports Supplements, Kimberly Mueller