ATHLETES: Overtraining can seriously affect performance. Researchers have identified several short term key markers that result from overtraining, including "impaired anaerobic lactic acid performance and a reduced time to exhaustion". [ 7 ] The same study discusses many other soon-to-follow issues including problems with uric acid levels, ammonia, creatine kinase, free testosterone/cortisol, growth hormone and so on. More subjective issues include excessively sore muscles and sleep and mood disorders. Again, overtraining is real and leads to real physiological issues.
The partition coefficient of the ester in question is important because is effects how long the drug itself stays in the system. If the testosterone transfers too quickly from the oil to the blood, the result is a sudden spike in testosterone which then rapidly drops once the dose has been used up. In the example of free testosterone injected into the muscle from a water suspension (as in Aquiviron, mentioned above), the testosterone is essentially immediately available to the bloodstream due to its low partition coefficient, and thus there is an immediate spike of testosterone which is used up quickly in the body.