Dan (and list) Your question is / was a large part of my dissertation research and the research I did when working on my post-doc. In general, the effect of actue exposure to altitude on distance running is VERY individualistic. Brief points: --Acute altitude affects highly trained distance runners much more negatively than untrained people -- i.e. trained runners see a larger change in VO2max and race time compared to untrained people. --WITHIN the highly trained population, the change in race time & VO2max has a large variation. For example, in an elite athlete cohort we studied at Indiana in the mid-90's, the individual changes in VO2max from sea level to a simulated altitude of 3300ft (1000m) ranged from 0 to just over 8%. --The likely cause of this variation is related to individual differences in pulmonary gas exchange limitations. A portion (around half) of elite endurance athletes exhibit a phenomenon called exercise induced hypoxemia (EIH). This, practially, means that these EIH athletes have less O2 bound to their hemoglobin when the blood leaves the lung (i.e. less O2 loads into the blood). --Why? Different theories abound and there are several mechanisms that likely contribute. The primary one (arguably) appears to be what is called decreased RBC transit time in the lung. This means that the athlete's cardiac output is so maximized with training that the blood cells move through the lung so fast (a short transit time) that there is not enough time for the O2 to diffuse across the lung to bing with the hemoglobin. --What it means for the athlete at altitude -- athletes who demonstrate EIH will be significantly more affected (negatively) at altitude -- even very mild ones, like 3,000ft. --While 3,000ft is not considered high enough to limit performance in the general population (which is true), EIH athletes in our study at 3,000ft had a significantly larger decline in VO2max, compared to athletes who did not demonstrate EIH. A practical example would be the results from the WC's in Edmonton in 2001 (Edmonton, I believe, is just short of 3,000ft). The times from that meet are (eyeballing) substantially slower than 2000 in Sydney or 2003 in Seville (despite the heat). This mile altitude issue was a significant factor for an athlete I coached at the time, Tom Chorny. Tom won USA's in the SC and got drilled in Edmonton. Of all the elite athletes I have ever tested in the lab -- well over ~300, Tom was the MOST negatively affected by altitude (in terms of decline in VO2max). We knew before he went he was going to be in trouble. --To answer your question of how much -- again it is individualistic. If you had a lab, you could test for EIH and know wich athletes would likely be the most affected. Look for SaO2 at VO2max falling in the low 90% range. --In terms of an AVERAGE -- while I don't have the data in front of me, I remember the average decline in VO2max at 3,300ft in our elite group as being around 3%. As a very general rule, the change in 5k performance is roughly half of the change in VO2max. So you could expect to see an average drop in time of your athletes of about 1.5%. (If you want to confirm these numbers for yourself, the study is published in Medicine and Science in Sports and Exercise, sometime in 1997) --For your other question -- can you do anything about it? Physiologically, the answer is essentially no. Kind of a bummer. You would get some mitigation of the decline if you could acclimatize to the altitude -- but that would take at least 14 days or so. Some other things that might help --- a) try to force a slower pace. In a more sit and kick race, the EIH athlete's "weakness" at altitude would be exposed less. b) consider focusing on a later meet. In the example of Tom Chorny, the NCAA's his senior year were at Boise, which is right at 3,000ft. We knew he would be impaired there, so we focused his peak more towards 2 weeks later at USA's in Eugene. In Boise, he did his best to finish 8th, but in a better / deeper field finished 8th (first collegian) at USA's in a new 7 second PR of 8:30. As a district race, is there any way you can get through to the next round, without worrying? If so, great. If not, maybe consider a focus on footlocker? Might not be prac! tical though. Best of luck, Robert Robert Chapman, Ph.D. Men's Cross Country Coach Adjunct Professor of Kinesiology Indiana University
________________________________ From: [EMAIL PROTECTED] on behalf of Dan Kaplan Sent: Mon 7/31/2006 4:58 PM To: t-and-f@lists.uoregon.edu Subject: Re: t-and-f: Altitude Training Symposium I've been meaning to ask a semi-related question. There's lots of data out there on the performance gains of training at altitude, and the effects of altitude on sprinting, but I can't find anything about its effect on distance running. Is there a percent formula (slow-down), or does it vary too much with each individual? We have our XC District meet at 3,000' feet this year, which isn't huge, but it's significant for people accustomed strictly to sea level. I'm curious how much slower we should expect 5k times to be, or if the modest altitude effect can be countered by extra hill work and higher mileage (strengthening the lungs and circulation). Dan http://AbleDesign.com <http://abledesign.com/> - Web Design & Custom Programming http://Run-Down.com <http://run-down.com/> - 10,000 Running Links, Fantasy T&F ------------------------------------------------------------ @ o Dan Kaplan - [EMAIL PROTECTED] <|\/ <^- ( [EMAIL PROTECTED] or [EMAIL PROTECTED] ) _/ \ \/\ (503)370-9969 phone/fax / / __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com <http://mail.yahoo.com/>
