Altitude and HR

I have the opportunity to go do 5 days of riding next week in CO, with a lot of riding above 7000’ and hitting plenty of 10k, and of course Mt Evans too (yikes!). Seeing that I live at 1000’, I know my power is going to be crippled quite a bit. Are HR zones valid at all? I did search and looked at previous comments, and did read Jakes blog post. Thanks for any info.

Also, if I kinda wanted to have accurate tss calculation, I’m guessing should drop my ftp in TP by 30%?


Heart rate won’t be as effected. Your power at certain heart rates will be lower. Also however it does take longer to recover. So heart rate may stay higher after any hard efforts.

Adjusting FTP by 30% might be a little much. Maybe 10% would be a good number to go with since you’ll be mostly over 7000ft.


I just ran into this podcast in altitude, may help some people out: