Originally Posted by BruceZ
Why would it? The energy for anaerobic activity comes from metabolic processes that don't require oxygen, and they are limited in duration by lactic acid buildup in the muscles. The new particles just deliver oxygen for use in aerobic processes as a substitute for breathing.
Right — this would have no direct effect on anaerobic
performance. However, it would allow an athlete to increase aerobic
output if the limiting factor thereof is oxygen delivery to muscle fibers, which is normally the case, and if the oxygen content per unit volume of vesicle laden blood is greater than that of fully oxygenated normal blood, which almost has to be true given the results of the study. In performance terms it would allow an athlete to, say, run harder before the anaerobic "kick" at the end, for as long as the pre-loaded oxygen vesicles continued to matter, so it would have the biggest effect on middle distance athletes, with none on anaerobic-limited performance and possibly not enough on long distance to make up for whatever the adverse effects turn out to be. (increased blood viscosity?) (I didn't see any indication that the technique increases the blood's oxygen transport capacity in a relevant way — rather, the study cited is using it as storage — though it might and if so would also affect the long distance athlete in a way similar to EPO doping, though of course it might be either more, or less, effective at that.)
It seems like it would have approximately the same effect as increasing muscle fibers' myoglobin levels (though not as useful because it would be better to have them inside the cells, rather than crowding out RBCs). We do know that endurance athletes have increased myoglobin levels, but I haven't seen anything about myoglobin doping actually occuring, perhaps because it's hard to do. (Selenium apparently does it a bit, but I don't know that athletes are using it.)
We also know that deep-diving animals tend to have far higher myoglobin levels than we do, by more than an order of magnitude. (human: 4–7 mg/g dry muscle; whales, ~100 mg/g) I didn't do the math myself but have read that if one somehow could increase myoglobin to whale levels that would be like adding about two full breaths of extra oxygen; it would seem the technique studied, which kept people alive 15–20 minutes, is equivalent to considerably more than that. So I guess the most obvious use, in theory, looks like it would be in free diving.
One amusing issue is that the article and study abstract (I don't have access to the full study) don't mention CO2
. If the particles don't take up carbon dioxide, and there's no reason to believe they would, then reliance on them would be associated with at least some respiratory acidosis, which might ultimately be the limiting factor for use by conscious humans, especially divers.