I’m sure there’s a smart thread or three on this and I just can’t find it here so hoping the community can help…
Just moved to Denver from Chicago 2 days ago. Went for a 5mile run but had to cut it short to a 5k as I was feeling awful. And a relatively slow 5k at that (about open 13.1 pace). Much could be attributed to lack of sleep, poor diet and stress from the past few days but wondering to what end altitude impacts performance? Is there a general rule of thumb on impact (e.g. your 5k time in CO will be 1min slower than at sea level)? Also, what about how long it takes to get acclimated to altitude such that you can train and race at previous levels? Anything else I should know?
Going to admit I’m not at all on an expert on this so I can’t say much, but I think I’ve heard 2 weeks has been said as appropriate time to get acclimated.
I moved to Colorado Springs from Michigan at the start of August and know how you feel. My first few days I struggled to run 3 miles at a pace slower than my marathon. It didn’t help that there was more elevation gain in those 3 miles than I generally get in my 10+ mile runs. Just keep going a few miles every day, drink a ton of water and after a few weeks you’ll be close to where you were at before. I’ve heard you’re about 10 to 15 seconds a mile slower than you would be at sea level once you’ve acclimated.
Did the same thing not too long ago, though for the third time going up and down. Should take you about 19-21 days to become acclimated. Stick to flat if ya can during then IMO. You should run about 13 seconds slower per mile after 1 mile (about 5-7 secs slower) based off NCAA charts and those are prolly pretty tight and tough so 15 secs is prolly easy to remember. Thats the hard part to get used to is your new normal. Intervals will seem harder and the CU team has been known to run 300’s instead of 400’s for speed workouts that focus on pace. If you are going back and forth to the midwest I recommend doing those for a sea level race. It is also drier out here so i tend to carry water more often. Where in Denver did ya end up? I am down in Littleton. Waterton canyon is my favorite place to run regularly. Boulder Running Company group runs are awesome down this way as well.
Welcome to CO. As others have said it’ll take you a couple of weeks to fully acclimate. Also keep in mind it’s very arid here too, need to hit the water more than you think.
There is a lot of misconception surrounding the concept of being “acclimated.” What that roughly means is that your body has largely completed the process of changing the blood supply to match that of someone who has lived here a long time. That is, it has made that adaptations that it can make. What it does not mean – contrary to many peoples’ wishes – is that somehow you can run the same speed at altitude as you can at sea level. That never happens. You could live in Denver the rest of your life and your lungs would still get less oxygen from a breath than you got at sea level. Thus, times are slower up here, even for the locals. Estimates vary, but 3% is a rough approximation of the speed loss from running at Denver altitude vs. sea level. As for the rate of acclimation, this varies. But, after a month or so you have done most of the acclimating that you’re ever going to do. As you will learn, some of this is psychological as you get accustomed to your new speed.
Altitude is another training stress, it takes time to adapt. It’s just like when you add intervals or some other new effort type into your training. Expect it to take 4 weeks till you feel on top of it. Usually it feels worse for the first few weeks before it get’s better. I’d recommend someone get here a day or two before a race rather than a week.
Altitude generally has a stronger relative effect on paces with an anaerobic element (10k pace and faster) vs just purely aerobic (marathon and slower). Basically, you don’t run fast times up here. NCAA has a calculator for collegiate qualifying times, and it is about 2% slower for Denver level. You’ll get used to it being just a bit slower.
Going down is great though, I’ve gone 10 seconds/mile faster at 10K pace, run a marathon without feeling any breathing stress. Running seems so much more fun from that instant fitness.
There is a lot of misconception surrounding the concept of being “acclimated.” What that roughly means is that your body has largely completed the process of changing the blood supply to match that of someone who has lived here a long time. That is, it has made that adaptations that it can make. What it does not mean – contrary to many peoples’ wishes – is that somehow you can run the same speed at altitude as you can at sea level. That never happens. You could live in Denver the rest of your life and your lungs would still get less oxygen from a breath than you got at sea level. Thus, times are slower up here, even for the locals. Estimates vary, but 3% is a rough approximation of the speed loss from running at Denver altitude vs. sea level. As for the rate of acclimation, this varies. But, after a month or so you have done most of the acclimating that you’re ever going to do. As you will learn, some of this is psychological as you get accustomed to your new speed.
Glad someone beat me to it.
Regardless, Denver is a great place to be with lots of oppurtunity
I’ve lived at 5500ft-odd most of my life (Johannesburg then Denver). I do notice significant performance differences when first changing altitudes. In those dim distant days when it mattered to me, the qualifying standards for SA 10k road championships were 34:10 at Johannesburg altitude, or 33:20 at sea level. That corresponds to my experience, about a minute over 10k at those speeds, 3-4% generally.
Used to go to university at sea level and return to Jhb for vacations, normally took about a week to ten days to adjust to the altitude again. In the other direction, typically would be about 40-50sec faster on an 8k run timetrial at sea level, after living/training at altitude for a month. After another month to six weeks at sea level, I’d lose the turbo and the improvement, boo.
Avoid HYPOhydration… not drinking enough water. Thirst is depressed somewhat during the early phase of acclimatization to altitude. Inadequate fluid intake reduces small blood vessel circulation, further complicating the issue of hypoxia.
Avoid HYPOhydration… not drinking enough water. Thirst is depressed somewhat during the early phase of acclimatization to altitude. Inadequate fluid intake reduces small blood vessel circulation, further complicating the issue of hypoxia.
Yes and no, There is an altitude induced diuresis (excess urination) that is an appropriate response to acclimatization but you are correct in that drinking additional water is worthwhile especially given the combination of both altitude and an arid environment. This especially applicable in the acute headaches that many people report once visiting Colorado.
This diuresis reduces total body water and blood volume which does (potentially) two things:
Decreases load on the cardiovascular system (increased HR and Blood pressure due to decreased oxygen concentration)
Increases hematocrit for potentially improved O2 transfer at the lung.
This is a short-term adaptation and typically plasma volume returns to normal ~ 1 week of exposure (regardless of how much you did or didn’t drink).
Once upregulation of EPO occurs, total hemoglobin mass ought to increase (there are responders and non-responders), bringing hematocrit back in line with a normal plasma volume.
I respectfully agree and disagree about the role of diuresis during the early phase at altitude. Initially, the diuresis promotes oxygen delivery to the brain via the central circulation. However, this requires blood pressure regulation in small vessels that reduces flow and oxygen delivery to other tissues like muscles.
Figure that for every 1% decline in “available aerobic power” you are going to get a decline in running speed of about 62% of that. For instance, at 5000’ acclimated individuals average a decline of 5.6% in power, which equates to 5.6% * 62% —> 3.4%. If you are used to running 7:00, that turns into ~ 7:15. Unacclimated at 5000’ the average is about an 8.9% decline, which turns into 5.5% slower. 7:00 turns into ~ 7:23.
Make sense?
As you can see, the biggest difference between acclimated and non-acclimated happens in the 7000’ - 10,000’ range. Not so coincidentally, that’s the best elevation for most of us to maximize the benefit of altitude.
Anyway, Denver is low as far as altitude is concerned. You should get to a point where it’s barely noticeable within 3-6 weeks.
I’m not a google drive spreadsheet master, but I think I did this right. You should be able to edit in the appropriate cell, A2. Put your pace in and it’ll spit out the corresponding pace at different altitudes for acclimated and non-acclimated.
Not that awesome. What’s physiologically awesome is that you can use your usual at-home training HR at altitude. It’s much more specific to the effect of altitude on YOU… not some chart average.
