Adjusting FTP / LTHR for training/racing at altitude

I have a question about adjusting individual TR workouts (and plans) based on altitude. FTP obviously decreases with altitude, but I wonder by how much? Is there a good rule of thumb? So far, I have avoided doing back to back Ramp tests to find out… :nerd_face:. But this is only looking at the training stress part… recovery part is also affected, so it’s tricky.

For example, during the week, I sleep/train at 5,500 feet. On weekends, I sleep/train at 9,000 feet with outdoor climbs sometimes taking me up as high as 12,000.

For outdoor MTB structured workouts, I only have heart rate unfortunately. Like FTP, does LTHR decrease as well with altitude, leading to different HR training zones?

In the past, I used rule that FTP decreases by 2-3 W per 1,000 feet and that might be true. But again there’s also decreased recovery at altitude… I’ve learned to avoid VO2Max workouts at altitude because recovery cost is too high. But even going over threshold a bit on Sat (Palisade for example) can really dig me into a hole and Sun becomes a zone 2 workout by necessity. This has caused me to fall off training plans multiple times. Ultimately, I’m hoping that Adaptive Training will help me sort out this problem more effectively!

Thanks for your help and insights team! Love the podcast.


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Not in my experience. I would keep the same LTHR.

The charts Landis posted are the usual adjustment factors, but there is a simpler rule which is 1% for every 1000 feet above 3k.

So your weekend training would need to be adjusted between roughly 4-7% lower from your usual home elevation just for simplicity’s sake.

You seem to have your head on straight by sticking to sweetspot and endurance riding for your weekends at altitude, and scheduling the harder work for when you are lower down. That’s pretty much an optimal environment to get faster tbh.

Hopefully you get to go down to sea level to race :sunglasses:


I use 1% per 1,000 ft. A good approximation. I use it in both directions. It would be great @Nate_Pearson if outside workouts sensed your elevation relative to where your home trainer is and automatically adjusted target power… as if you didn’t already have enough to work on.


Older thread, but wanted to throw a related question in about racing at altitude.

I live at sea level, and have a race coming up at 7500’, and will have 4.5 days to acclimate. I’m probably going to “reduce” my FTP to 88-90% and base my pacing off of that. Bassett says a low of ~85.5% un-acclimated for that elevation, 89% acclimated, some people say 1% per 1000’ so that range is roughly 85.5% - 92.5%. I’m targeting 8 hours, so that’s probably 75%-80% NP based off of my adjusted FTP.

What has been your experience with impact on muscles, how tired you get, when racing an event at altitude? I get there’s less available oxygen, but at the same time my muscles (from a power / power endurance perspective) are used to putting out higher power for the same duration. Have you found your target NP / Intensity Factor you can put out to be similar to sea level after adjusting your FTP?

I get there’s a lot that goes into it, but any advice for setting a target NP for an 8 hour race at 7500’? I did 6 hours at ~1800’ at a reported 83.6% NP of my sea level FTP earlier this year. Definitely crushed me though and NP was dropping by the minute at the end.

That might be less than ideal for acclimation. IIRC from podcasts the perception of most was to better stay longer (1-2 weeks) or arrive the day of or the day before. So maybe keep that in mind and calculate with some caution.

I know that gets said, but I do have some altitude experience and day before / day of would be a hard no for me based on my own personal experience. I’m much, much better off 3-4 days in.

Went to Leadville in 2020 and Blood O2 was significantly low 18 hours in and I was sitting on the couch out of breath. Was back to Normal by day 3-4. Coming up the morning of would mean getting up at like 2 in the morning and driving 2-3 hours to make a 7AM start, so not practical whatsoever.

7000-8000’ has never been an issue for me either, I do a trip to the mountains of Montana and Wyoming almost every year, albeit never for biking where I’m measuring power output.

I want to bump my own thread bump here to see if anyone can weigh in.

When you’re a Sea Level athlete and race at altitude, I’m trying to get a better sense of the “practical” impact and how it feels. I’ve spent time at altitude plenty, but never biked / raced where I can say I know how it’s going to impact me.

I’m from sea level, if I go to 10,000’ I’d plan to discount my FTP to approximately 80% based on Bassett (Assume that’s correct for a second - I know it’s an estimate and there’s acclimitization, etc.). Let’s say I then compare an 80% of FTP effort. At sea level - I’m used to training at a higher power. At altitude that 80% FTP is correspondingly lower. Does this affect you the same way? For me, it’s always leg burn moreso than heart rate that gets me Even my V02 Max workouts I usually end up 20-30BPM below my max heart rate. Would I expect the same leg burn? Or, would I expect my legs and muscles to be used to the higher power, but with less oxygen be experiencing a higher heart rate, much heavier breathing, and trouble getting in enough Oxygen?

At the end of the day, I’m thinking about how to pace at altitude. If I think I can do 80% NP for the effort while not going over FTP at sea level, is it reasonable thinking I could do 80% NP of my 80% FTP at altitude?