Originally Posted by
bartolomei
EPO can actually increase after several series of apnea as shown in the study LGHT above linked to it, but the question is for how long does this increase last and does it translate into better physical performance. To me, it sounds very unlikely this would have any practical meaning.
However one goes about creating extra endogenous EPO in the kidneys, its effect is to initiate the creation of red blood cells (RBCs), which when mature will enable the blood to carry more oxygen and thus increase performance. The trick is that our bodies are way too smart and are quick to scavenge stuff that is unneeded, such as muscle and RBCs. So if you don't keep doing whatever you did to create the extra EPO, as soon as you stop doing it the body will eat up those excess RBCs even before they fully develop. Lower EPO is a signal to do that.
I don't know the answer to how frequent the various interventions (apnea, VO2max intervals, high altitude) need to be in order to get the initial crop of RBCs developed and then to maintain their presence in the blood and thus get the performance improvement.