No, that's not an endorsement or a suggestion -- but it's the interesting implication of a new study from the University of Zurich (abstract here; press release here).
EPO is (in)famous as a blood-boosting drug: it's produced naturally in the kidneys, and it tells your body to produce more red blood cells and consequently boosts your ability to transport oxygen to your working muscles. If you're an endurance athlete, it's clear how that will make you faster. But the new study shows an immediate performance-boosting effect (higher VO2max, longer time to exhaustion in a treadmill test) for mice who were given a single high dose of EPO, totally independent of any changes in blood parameters. The evidence (from other studies as well as this one) suggests that EPO crosses the blood-brain barrier and activates certain areas of the brain, and even stimulates neuron growth. In effect, the researchers argue, EPO is capable of creating an immediate reduction of "central fatigue" -- the portion of fatigue that's mediated in the brain rather than the muscles.
This isn't the first research to look at EPO's effects on the brain; for example, a previous placebo-controlled study found that EPO significantly increased motivation in endurance athletes. But there's a catch before we assume that these new results apply to humans too. Half Marathon Training tried to test exactly that, but failed to find any brain-mediated performance boost in humans. The authors of the new study suggest two possible reasons for the discrepancy:
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- The dose in the human study was too small to produce sufficient levels in the brains of the humans. Adjusted for weight, the dose was almost 200 times higher in the mice.
- The effects of central fatigue (the hypothesis that "glucose, dopamine, and serotonine as well as noradrenaline levels in the brain play a key role in limiting maximal exercise capacity") are well-established in animals, but not clear in humans. It may be that other factors limit human performance before these particular factors (which are "fixed" by EPO) come into play.
So what's the takeaway? What seems to be clear is that EPO does have effects far beyond simply boosting blood:
In the past, it was thought that the only function of Epo is the regulation of the red blood cell production. Very recently, however, Epo has been found to exert regulatory effects in different organs, such as liver, heart, kidney, spleen, lung, bone marrow, reproductive organs, and brain.
If nothing else, this tells me that it's a very bad idea to play around with this drug. And it may also help answer the longstanding question of why Running We earn a commission for products purchased through some links in this article. Sadly, the cheaters always seem to be several years ahead of the scientists.
