Altitude & Power

Hi...

So I got and read the 'training & racing with power' book, but found a topic of interest wasn't covered.

Altitude. Specifically what effects it has on power & performance. I live at 5600 feet and train at altitudes ranging from 5200 to 10,000+. My favorite ride actually is a climb starting at about 6700 feet that tops out at 10,600. Not surprisingly, the second half of this climb is always disproportionately difficult.

That said, I browsed and searched for articles, coming across one of particular interest.

http://midweekclub.ca/powerFAQ.htm#Q17


So what would you suggest happens to one's sustainable power - specifically, on this climb from 6700 to 10,600+ :would it be logical to assume my FTP would drop by 5-10%???

Also, would it then be prudent (or accurate) to do the tests and data collection for the Critical Power curve at an altitude comparable to the one I live at ~ 5600 feet?

Finally, if I go to florida on vacation and ride, should I expect my sustainable power to be 5-10% higher than at home?

I'm sure there are folks on this board who live at altitude and/or compete in such, so let me know what you think

Can't help you, as I ride at sea level and the highest hill on Long Island is all of 401 feet.

But to complicate the question, what happens if you ride below sea level? I'm doing a charity ride and day 2 is along the Dead Sea, 1600 feet below sea level. Will sustainable power increase?

One of the members of this forum has done some work on this topic. The work he shared with me may be proprietary, so I don't want to share his analysis. Hopefully, he'll spot this thread and offer some help with your question.

Is there any general 'non-propietary' information you can share?

I have been reading about altitude training and the like, which I'm not sure is entirely applicable given that I live at 1700 meters. What I have read suggests an increase in red blood cell counts because of extra EPO the body produces. The rationale goes apparently, these increases will remain in the body for 7-14 days even at sea level, providing a hypothetical advantage.

I'm certainly jealous of your terrain. Don't be like RDO and rub it in the faces of all us flat-landers.

I'd be afraid that any hypothetical advantage would be offset by the additional heat, humidity and air resistance encountered in Florida, but I'd be interested to see what the expert has to say on the matter.

Isn't the addage 'Live high, train low'?

There are two questions in play here. One is what one might do to gain an advantage through altitude training or use of altitude tents and the like. I have done no work in this area although I think no less than Andy Coggan has experimented with altitude tents so I would have to conclude that there is a physiological basis for it. The second question, and one of keen interest to me, is how altitude should be taken into account in the formulation of optimal TT pacing strategies. It was in the context of my work on this latter subject that some information has been shared with me and I think the author considers it to be proprietary. So, in short, I can't be of much help but others on the forum have done work in this area. Hopefully, they'll spot your thread.

Jeez, these guys who think a highway overpass is a mountain are sooooo sensitive.

I am no expert, but this is fairly moderate altitude. Though I'd expect you to be favored by the fact of living and training at this altitude all the time, I wouldn't expect the difference to be *that* significant compared to sea level. 50% sound like a lot to me. But again I am no expert.

All I know is that when looking for a destination to hold an altitude training camp, we aim at levels that are above that.

That's consistant with what I have learned too. I wouldn't bet that my knowledges are still up to date though. last training camp I got involved in was held in 1998.

Bah! I put a 29" front wheel on, and now I get hill training wherever I go.

Well, it's nearly trainer season again. You can put a phone book under your front wheel and get some hill training that way too.

I am speculating perhaps 5-10% more in terms of power for me going from 5600 feet to sea level.

If it was 50%, then I suspect all my neighbors would be riders and clearly they aren't

Au contraire! I lived in Florida for almost 10 years, so flatlanders have my empathy

LOL - now now....


All kidding aside, my concern is that gathering data at 8,000+ feet to create a critical power curve would skew things a little bit to be lower than in actuality. Then again, I ride a lot at higher altitudes than I live at. Thus, maybe it is useful to know what power I can sustain at those heights so I can pace my efforts/intervals accordingly.

Going from 5600 ft down to sea level, believe you'll produce more power, but find it's not enough to make up for the increased aero drag. EG, if air density increases 15%, that also means your aero drag increases by that same factor at a constant speed.

I'm guessing that you'll get some boost in power from the increased O2, but not the 15% boost needed to offset the increased aero drag, resulting in slower average speeds on the flats for what feels like a similar levels of output. Slow-speed climbing should improve, since aero drag really isn't a factor below about 10 mph.

In fact, aren't some of the fastest hour record runs done at altitude? Thought I read somewhere about records being questioned or annotated at high altitude venues.

AS RD will tell you, I do all my training with my head in the clouds. But even training at that altitude doesn't seem to improve my FTP much.

Indeed the hour records have oftentimes been set at high-altitude venues - Mexico City, several times actually.

The sea level question though is more of a novelty to me at this point. I'm not about to enter any kind of event, I'm making enough of a git of myself as is!

What I am much more interested in is:

a) ideally where, altitude-wise, to perform my FTP tests.....at the altitude I live at? at a higher altitude to mimic where I frequently ride? something else?

b) should I expect a slight decrease in sustainable power by riding anywhere from 2000-5000 feet above where I live? and if so, then adjust my pacing accordingly.

RD has reserved comment on this for reasons already stated. Anyone else have ideas/suggestions/comments on the two questions posed above?

IMHO the ideal place to perform FTP (or better yet CP) tests is a place where you can do it often under similar conditions and in a reasonable amount of time. What difference does it make if it's a bit more accurate at higher elevations if you can't reproduce test conditions as often or have to make a bigger ordeal of heading away from home for testing?

Probably, after all most folks feel a 5000 foot elevation gain (think of football teams visiting denver and sucking O2 on the sidelines). I suspect you'll adjust your pacing pretty easily when a given theoretical duration/intensity is too hard to sustain.

I live at a similar altitude (6200') and we have passes with similar elevation gains on local rides. I do my power (or in the old days HR) testing near home in a place I can get to readily year round. I establish working ranges for power or HR and ride as best I can in those ranges but make minor adjustments by listening to my body. If I'm suffering when I shouldn't be I tone things down a bit but still try to stay within the target zone. The training power ranges don't have to be held to the closest watt to give positive adaptations.

Remember all these data collection and training analysis tools are amazing but in the end the only data that really counts is what's recorded in your legs and lungs. Don't become a slave to the last digit of these tools.

Good luck,
Dave