When people engage in extreme exercise such as long distance marathon running or weight-bearing exercises, they run the risk of causing serious damage, both to their muscles and to their kidneys, due to the stress imposed on their system in trying to maintain adequate energy to fuel the muscles. It has become common practice to measure the levels of creatine kinase in the blood as a known indicator of potential damage . A person whose creatine kinase level gets alarmingly high will likely need immediate medical attention to avoid renal [kidney] failure.
The cause of the kidney failure is most likely myoglobin that has been dumped into the blood stream by compromised or dead muscle cells, due to rhabdomyolysis. If too much myoglobin is released, particularly with inadequate water supply, the myoglobin can block the renal filtration system causing a condition known as "acute tubular necrosis." The problem can be easily detected by observing the color of the urine, which will be dark brown. A study published in 2009 showed that, in rhabdomyolysis, the damage to the kidneys involves direct interaction between myoglobin and the mitochondria in the kidney cells . The resulting oxidation of the mitochondrial membranes leads to respiratory failure and subsequent cell death.
Myoglobinuria is the term used to describe the presence of myoglobin in the urine, usually due to rhabdomyolysis. According to , 15% of patients with severe myoglobinuria develop acute renal failure, and it is associated with high mortality rates. Dialysis or intravenous fluids must be introduced fast enough, or the person will not be able to recover.
As early as 1991, a group of Japanese researchers  demonstrated that coenzyme Q10 could be administered orally to protect rats from muscle damage due to strenuous exercise. They also noticed that rats that were administered coenzyme Q10 did not have elevated levels of creatine kinase and lactate dehydrogenase, whereas the control rats did.