PaulDavis wrote:
Last two days have been the opposite of confidence building. We arrived in Santa Fe yesterday (altitude 7400'), partly to look at real estate and partly to escape the polar vortex to the east. Not sure how much of the "impact" of altitude is in my head versus my cardiovascular system, but either way ... so hard to run much faster than 9:30 min/mile, if that. A few days ago, I managed sub-7 min/mile with a bit of effort, and only a few hundred feet above sea level. Also, running in the mostly-dry sand of Santa Fe's arroyos is very pretty but also hard and slow.
Still, 1 run up, and still at N-for-N. Arches Ultra is on the table for next weekend, but I can't decide about running an ultra in near freezing temperatures (albeit with sun).
7400 feet is substantial.
I did an "altitude effect" test in 2015 in Bormio Italy. The climb up Stelvio goes form Bormio at 4500 feet to the summit at ~9000 ft. I figured that climb would take me 90-100 minutes based on the VAM (vertical altitude meters I can sustain....1000-1150m per hour was what I could do at the time, so this should be no problem).
Next thing is that I had raced several half Ironmans that year at 210-227W power for ~2:30 depending on course. As such I knew that 220W for 90 minutes with NO SWIM OR RUN should be "easy".
I started out at Bormio with my power meter pegged at 220W. This seemed easy enough until I got over 6000 ft altitude at which point it became laboured. By the time I reached 7000 feet, the effort of 220W which is my half IM race pace, felt harder than sprint tri effort, but doable. Once I massed 8000 feet, it felt like I was riding a 10 mile ITT. Once I was at 8500 feet, the perceived exertion at 220W was as if I was running the final half lap of a mile running race. It was insane pain AND my power kept dropping below 220W which was my "steady" half IM race pace.
The reason why I was doing this, 3 weeks before IM Lake Tahoe was to establish a power deration "graph" in my head between 6000 feet and 7700 feet which I believe was the high altitude on the Brockway climb at IM Tahoe. I am glad I did it, because on loop one 200W up the climb felt "easy" but I knew I had to respect the altitude and dial back to 180W max which felt like crawling. On loop 2, I could barely hold 180W and I was passing all kinds of people. On that day I averaged a puny 165W for a 5:39 bike split on the crazy course.
Anyway, just wanted to share some power vs altitude data which would roughly map to altitude running. As a point of reference my FTP at the time was around 265W, so at 7500 my 'effective FTP" was down barely to 220ish watts.....so you can equate that deration to your running effort and see the picture.