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The 80 percent rule :0)

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Re: The 80 percent rule :0)

Postby ajkagy » Thu Sep 12, 2013 11:57 am

I would think lung capacity would be a huge limiting factor as well. Some people will just born with larger lungs.
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Re: The 80 percent rule :0)

Postby madbuck » Thu Sep 12, 2013 12:17 pm

ajkagy wrote:interesting...so in other words, if you've lived at 10k ft. for a long time you'll still never be as fast as you are at 10k ft. then if you lived at sea level.


Yes! All else being equal...
Of course, as you live and train at the higher elevation, you'll achieve efficiencies that would have made you even faster had you remained at (or when you return to) sea level. But if you're working really hard for an objective goal -- e.g. a 3-hour marathon or 5-minute mile -- training for and achieving that goal is more difficult at higher elevations under otherwise similar conditions at lower elevations.

Of all the misconceptions about altitude and acclimatization, that's a good one to stake in the ground: oxygen is an ergogenic aid!

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Re: The 80 percent rule :0)

Postby pvnisher » Thu Sep 12, 2013 5:54 pm

In addition to all the other posts, considerthat mosy peoplr dont run/bike for the amount of time it takes to hike up and down. Running 45 mins is great, but not direct correlation to hiking 8 hours.

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Re: The 80 percent rule :0)

Postby Peak_One » Thu Sep 12, 2013 8:23 pm

pvnisher wrote:In addition to all the other posts, considerthat mosy peoplr dont run/bike for the amount of time it takes to hike up and down. Running 45 mins is great, but not direct correlation to hiking 8 hours.


My main training for long CO hikes/climbs is intervals or either running or stairmaster with weighted pack. Usually spend about 30 minutes or less, but hit it pretty hard with a 2:1 slow/max ratio. I don't think there is anything I would want to do in Nebraska that takes 6-8 hours.

This has served me well. I can go hard by day 2, although I will be a bit slower and won't really like it, and by day 3 or 4 I feel fully acclimated.
"The best climber in the world is the one having the most fun!"- Alex Lowe.

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Re: The 80 percent rule :0)

Postby Summit Stomper » Thu Sep 12, 2013 8:57 pm

I used to run stairs in the winte when I lived in Anchorage, Ak. I would do 14 laps of 6 flights. I tried all types of combinations to increase my speed with a goal of beating my best time from the year before. If I trained 3x per week, I could really start improving my times. I did this for several years. Then in 2005 when I moved to Colorado, I started the same routine; lived in Alamosa for 1.5 years and now Colorado Springs area. I have never ever even come close to what I did in Alaska. I've always wanted to try again at sea level after a few months of great training here in Colorado, just to see if I would be able to blow the socks off my previous sea level times.

I also found that when I hike at what would seem to be similar pace/elevation gain as I did in Alaska; I am totally out of breath in comparison.

It's interesting to see how the body reacts to the altitude for sure.
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Re: The 80 percent rule :0)

Postby Dark Helmet » Thu Sep 12, 2013 9:04 pm

ThuChad wrote:My completely unscientific theory is if I can run an 8-9 minute mile without stopping at 1000 ft. For X distance. I can hike comfortably the same distance of X at altitude.



that's pretty much my experience... my half-M race-pace is about 7:20-7:30, and I'm comfortable at a hard-hiking pace up to 12K ft.

I struggled a little above 12 on Pikes last year, but most 15 mile hikes are on their way down by the time you get to the 10-mile mark.

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Re: The 80 percent rule :0)

Postby Alby426 » Fri Sep 13, 2013 5:41 am

Ok,as expected, most of you dissicated the original post scientifically and, made complicated analysis of what happens up there but, go explain that to someone that is struggling and, can't think straight.
Here is what I said:
"Please, don't try to dissicate this with complicated scientific analisys, just keep it that simple as, at that altitude, when you explain it, the lack of oxygen also affects cognitive abilities "

Effort level is a very generic, subjective, simple way to explain physical activity. 100% is the maximum one can do, 80% is the sustainable effort most can do.

The explanation I wrote, is great for explaining hikers, up there where the cognitive abilities are reduced, why, when someone struggles, is doing so.
I also found it to be very easy to understand for 90% of hikers that are not fitness fanatics. I can analyse effects on body on a perhaps deeper level than most, but, I also understand that there are many variables that are unpredictable.
Next time you are up there, think about what I said, don't over think it and, immagine having to explain it to someone else.

Cheers! :)
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Re: The 80 percent rule :0)

Postby jlarson630 » Fri Sep 13, 2013 6:21 am

Alby426 wrote:The explanation I wrote, is great for explaining hikers


Ya I agree. I have always used a basic 20% less atmospheric pressure/7000ft of elevation gain. The actual function for change in atmospheric pressure/change in height is an exponential function (though fairly linear) that also takes into account a few other variables such as temperature. When people come in from out of town, the 20% less rule always lets me give a quick explanation for fatigue.

On another note, I don't run too much but always love to go back to the Midwest and go for a run the day I get back. I feel like superman. It wears off just as fast as acclimation sets in though so ~10 days later a lot of your high altitude training advantage is gone.

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Re: The 80 percent rule :0)

Postby madbuck » Fri Sep 13, 2013 8:23 am

"There's less oxygen per lungful of air at higher elevations, and people that live at higher elevations are more adapted to it."
That's what I've used as a simple explanation.

I'm afraid you've made up some assumptions, and I think there's a slight English language issue; calling it a "Rule" and then asked us to accept it without questioning does not make it so.
I'm sorry, I know you mean well, but as a scientist, scientific literacy is important to me even more than mountaineering. I'm not trying to be combative, but accurate, especially with shared and perpetuated information.

Trying to be helpful: you named it the "80% Rule" but the only time you mentioned 80% is in respect to effort. It sounded like you were mixing numbers quite a bit, and this does not describe anything about the change in oxygen with respect to elevation. "jlarson630" above, though, does:

jlarson630 wrote:I have always used a basic 20% less atmospheric pressure/7000ft of elevation gain. The actual function for change in atmospheric pressure/change in height is an exponential function (though fairly linear) that also takes into account a few other variables such as temperature. When people come in from out of town, the 20% less rule always lets me give a quick explanation for fatigue.


7000' has (very roughly) 80% of the oxygen per fixed volume of sea level; and 14k feet has very roughly 80% (more like 76%) of the oxygen per fixed volume of 7000'. If we want a mnemonic label for ease of remembering, it makes sense to label the whole relationship: 80%/7k-feet "Rule" -- or 20% less/7000', as jlarson describes. Now that's an easy way to remember something accurate!

Cheers as well, and have a good day!

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Re: The 80 percent rule :0)

Postby Alby426 » Fri Sep 13, 2013 11:31 am

Don't over think it :) . This is designed to be a way to explain it, very simply, to other people.
I understand the science just as well as anyone (I am also a pilit, an aircraft mechanic snd, It is very important to understand Density Altitude).
Don't use my explanation as a scientific description but, just to let average hikers know why they struggle. The scientific explanation Horse has been beaten way out of here in this site already.
It is simple: one can sustain 80% effort level during excercise but, up un the mountains, they need to realize that 80% becomes 45% for a sea level person without acclamation.
Once that is said, tell them to slow down and, mantain a sustainable pace, that, may seem too slow.

I have encountered many hikers that were either struggling or angry at them selfs for not being able to hike faster, even though they are normally fit. The most common problem I have encountered is that they go too fast and, try to go at 80% of their abilities. At that rate, they burn themselfs out fast. Trying to explain difficult scientific theorem at that moment is impossible. Understanding how the same ammount of oxygen is still in the ambient air per mass but, mass is affected by pressure and humidity, with, thrown in the discussion the non-linear effect on pressure with altitudeand, on top of that discuss the effect of latitude is way too complicated. The explanation I came up with simply works. Struggling hikers get it.
This gives a simple quantitative value to the effort level required by a person. To say that there is less oxygen per lungful is still too vague for most.
Yes, calling it a "rule" is a stretch but, for the purpouse of making a point, that word works!

See you all up there.
Last edited by Alby426 on Fri Sep 13, 2013 12:43 pm, edited 1 time in total.

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Re: The 80 percent rule :0)

Postby madbuck » Fri Sep 13, 2013 12:10 pm

Alby426 wrote:It is simple: one can sustain 80% effort level during excercise but, up un the mountains, they need to realize that 80% becomes 45% for a sea level person without acclamation.


Again, what is the source of 45%, or the 55% for people who live on the Front Range? You said not to overthink it...but didn't explain where this number comes from.
To discuss science, we must be clear on the assumptions before teaching other people.

Have a good day!

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Re: The 80 percent rule :0)

Postby Alby426 » Fri Sep 13, 2013 12:50 pm

Ah, yes, the wat I came up with that approximate number is: 80% af sea level, then if at 14000 feet there is 60% atmosphere, then 60% of 80= 48 (45 for more impact) %.
For those that live in the Front Range, since we already lost 15%, the equation is more like: 70% of 80 (effort level) = 56 %.
I exagerate the numbers a tid bit to make the point.
know that I can be confusing but, I hope I was able to explain the numbers :mrgreen:

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