Any of the medical folks on the board care to comment on CVAC Pods for acclimatization? These pods involve a protocol where you cycle through varying barometric pressures, working your way up to higher pressures. They aren't cheap to use--currently about $40 a session.

Here is a summary from another board.

Here are some relevant studies:

http://www.ncbi.nlm.nih.gov/pubmed/19364183

This study reported an increase of about 9% in arterial blood saturation after seven weeks, though this was at 4570 m. The greatest effects appear to be at high altitudes, higher than those at which GTs are generally raced (even the recently-concluded US Pro challenge did not race at elevations anywhere near that high, and much was made about how the elevations were greater than the Euros had ever experienced).

Arterial blood saturation refers to the proportion of oxygen-binding sites on the hemoglobin molecule which are filled. So it is a way of increasing oxygen transport that does not involve increasing red blood cells, but rather in effect increasing the efficiency of the red cells naturally present. However, that 9% increase might not necessarily result in an equivalent increase of oxygen delivered to the tissues; it depends on the efficiency of unloading the oxygen. Assuming it did, though, it would be equivalent to increasing hematocrit from 45 to 49. That would probably be better than blood doping in the passport era.

http://www.ncbi.nlm.nih.gov/pubmed/18091011

This study reported a 16% improvement in TT ability. It was not clear to me from reading the abstract whether this was time; the values decreased, consistent with it being time, but only gave two places, whereas time is usually given in minutes and seconds. Also, this performance increase was accompanied by only about a 3% increase in arterial saturation, which should not be nearly enough to account for that big an increase in TT performance.

http://www.ncbi.nlm.nih.gov/pubmed/19461532

Another study by the same group found no performance benefit, but the hypobaric treatment was only for 1 week and I believe did not involve the pulsing changes in pressure used in the CVAC. This same group has also studied the effect of blood doping on performance.