If you are going to be spending time over 8,000 feet and are used to sea level, you may want to speak to your doctor about getting acetazolamide to take to lower the likelihood of mountain sickness.

Living at sea-level, I flew to Denver with my wife one day and we started a tour in the Rockies the next with 12,000' of climbing up to 9,500' ASL the first day of the tour. Subsequent days went higher. We didn't notice much difference, except for being slower for a given level of perceived effort. There were 8 others with us on that tour, all from low elevations, and none had any difficulty over the week-long tour.

I was so disappointed when I opened this thread .................................Bike Bong

Thanks! I am thinking of either doing the June lake loop on the way up on Friday as a training ride, or Sunday on the way back. It sounds like I will have enough on my hands just finishing the century without a few extra miles thrown in. Thanks for inspiring me!

Perfect! A word of advice. If you want to take in the Loop, I suggest doing it clockwise, starting from the north ... like this:

https://ridewithgps.com/routes/1436943

The initial climb isn't all that pleasant, but when you're done, you can grab a snack or water at the June Lake Junction, and from there, the way through the loop is mostly downhill and way fun.

Joe Dombrowski, leader of the Sky team at the Pro Cycling Challenge in CO, had to drop out this morning when he started coughing up blood. He had a bloody nose two days ago during the ride. Even the pros don't always have a good result when riding at altitude.

I live at about 300 ft elevation. When I visit home in Idaho the elevation starts at about 3000 feet, and I frequently do a climb up to the local ski area that goes up to 6000 feet. I don't have any issues doing that. However I rode a couple of passes in the Sawtooths that got up over 8000 feet, and I was definitely a bit gassed going over those. It's hard to describe. I wasn't winded or anything. It just felt like I didn't have any "push" in the legs.

Although no expert, I agree with those who mention acclimation to the altitude. Several weeks ago I had two friends who ran 50 miles (ultra marathon trail run) in Leadville, Colorado. They started at approximately 10,000 feet and went up and down over 12,000 feet. One friend was able to spend a month in Breckenridge to acclimate, but the other only had time for a week of acclimation. They are similar in skill and train together. The one with the month of acclimation completed the 50 miles in 11 hours, the other in 13 hours (and even though it was July he suffered from hypothermia from being caught in a rain/hail/lightning storm). Both live in Orlando area (sea level).

This was one of my hardest 10 rides (and half was downhill).

And speaking of downhill, you can descend like a demon in the thin air at high altitude!

More comments today from Colorado and Pro Cycling Challenge. David Zabriskie threw up a couple of times, other riders with problems, complaints about low power output, etc. Even the Axel Merckx was complaining about headaches just driving the team car.

The altitude is really sorting the riders out in the ProChallenge this year. Jens Voight said that 2 weeks prior to the race was the minimum time to adapt to the altitude they are riding in. I read that Cannondale and several of the Pro circuit teams did that this year, Sagan's results seem to prove this one out. If only Jens had held on in that break a few days ago................

Bill

I live about 300 ft elevation but when I go up into the Sierras to ride (6500-8500 ft) I never have had elevation sickness but I get winded way faster and notice less power output. I'd say the main thing is to realize you will go slower and take that into account. Once I stopped pushing to stay at my sea level speeds and accepted I would be slower I stopped burning myself out in the first part of the ride it helped a ton. I feel after a few days at elevation the constantly winded feeling lessens for me. I also seem to need more nutrition at elevation...

I live at sea level, hike mostly at 4-5000 feet. I start to suffer at 7000 feet. (By the way, is anyone going to take issue with the statement that alpine (i.e. downhill) skiing is more intense than cycling????)

I eat marijuana for diabetic nerve pain, I try not to ride my bike high, but if I do I walk my bike when crossing busy streets lol,,,i know i know you meant high altitude lol