hello monkey (is that mr.fork?),
regardng freediving at altitude, the higher you go the faster you get dehydrated (due to the decreasing air pressure) thus be sure to watch your fluid intake. dehydration can become a serious problem all on it's own at altitude, hypoxia and diving issues aside.
additionally, acute exposure to low air pressure (i.e., low partial pressure of Oxygen) can cause altitude sickness thus the hypoxic stress of freediving could exacerbate your risk. gradual acclimatization, to both the altitude and the freediving at altitude, is likely the safest strategy to avoid any issues. as long as you can avoid altitude sickness the benefits to your training should be pronounced.
given both altitude and freediving can result in pulmonary edema i wonder if there is an increased risk of barotrauma or other lung-related issues while doing both (i.e., freediving at altltude)? hopefully some of the wise physiologist-types can chime in here.
check out this article by sebastian naslund detailing a recent trip to the himalaya and the resulting effects of altitude on breath-holding. i don't think they did any diving per se, however, they did some breath holds while at elevation. they also took blood oxygen saturation readings both during and after the trip.
freediving and hypoxi
some other great freediving articles on the main site as well:
Freediving - articles, courses, news, stories, equipment, inspiration
anyway sounds like it would be a great place to do some diving---be sure to follow up with a trip-report detailing your experiences of training at altitude.
cheers,
sean
vancouver, canada
ps.
looks like others have had similar ideas---here are a couple trip reports:
Divernet | Free Diving | ALTITUDE WITH ATTITUDE
Freediving in Swiss mountain lakes, Rodi 2005
http://forums.deeperblue.net/general...tml#post242245
calculations related to cw at elevation
