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2009-10-20 8:11 AM
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Subject: RE: Elevation change per mile difficulty?
Pector55 - 2009-10-20 10:05 AM

One question about road steepness.  I believe there is a definite difference in a road's stated "grade" versus the actual.  Someone help me out with this but basically, the incline is a rise over run calculation but it's often stated as the -1 TAN or something where 45* = 100%. 


Grade is simply rise/run; therefore an angle of 45* would give 100% as the rise and run would be the same.  You can also use trig for this but rise/run is the easiest.

Shane


2009-10-20 8:40 AM
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Subject: RE: Elevation change per mile difficulty?
gsmacleod - 2009-10-20 9:11 AM
Pector55 - 2009-10-20 10:05 AM

One question about road steepness.  I believe there is a definite difference in a road's stated "grade" versus the actual.  Someone help me out with this but basically, the incline is a rise over run calculation but it's often stated as the -1 TAN or something where 45* = 100%. 


Grade is simply rise/run; therefore an angle of 45* would give 100% as the rise and run would be the same.  You can also use trig for this but rise/run is the easiest.

Shane


Correct, as I stated it's just a rise over run calculation.  I now remember what I was thinking about.  I'm thinking about the angle in comparison to grade.  That is where a 45* angle yields a 100% grade.  I was thinking of it in terms of a claimed grade of 31* at Savageman.  It's easy to think of that as a 31* angle but in reality that is the grade but the angle would be around 17(ish)*.    It's not relevant to the discussion so nevermind.
2009-10-20 9:07 AM
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Subject: RE: Elevation change per mile difficulty?
trinewby - 2009-10-19 7:07 PM
Breckview,
What problems have you seen with altimeters providing accurate elevation data?  They are far more accurate than non-WAAS GPS signals.

Greg


Barometric pressure, the weight of the air above you, is not static. When you're standing still and the elevation reported by a pressure-based altimeter changes, it just measured barometric pressure at a different level. But in order to measure elevation, the device must assume that pressure is static. By design, doing so is just an approximation.

Computing "elevation" is pretty easy for any device because a small error usually isn't very important when taking a spot elevation. (Unless of course you're trying to navigate by comparing spot elevations to map features and a mistake has serious consequences which is common in mountaineering.) But when a device measures say 1950 feet and then 1970 feet, it has no idea if that 20 foot climb was real, if pressure just changed a bit, or if the mechanism it uses to measure pressure just isn't all that accurate. The device can either count the climbing as real which would result in an enormous amount of false climbing, or use an algorithm to filter it out. But any filter algorithm will also filter out real climbing as well.
2009-10-20 9:07 AM
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Subject: RE: Elevation change per mile difficulty?
Pector55 - 2009-10-20 9:40 AM
gsmacleod - 2009-10-20 9:11 AM
Pector55 - 2009-10-20 10:05 AM

One question about road steepness.  I believe there is a definite difference in a road's stated "grade" versus the actual.  Someone help me out with this but basically, the incline is a rise over run calculation but it's often stated as the -1 TAN or something where 45* = 100%. 


Grade is simply rise/run; therefore an angle of 45* would give 100% as the rise and run would be the same.  You can also use trig for this but rise/run is the easiest.

Shane


Correct, as I stated it's just a rise over run calculation.  I now remember what I was thinking about.  I'm thinking about the angle in comparison to grade.  That is where a 45* angle yields a 100% grade.  I was thinking of it in terms of a claimed grade of 31* at Savageman.  It's easy to think of that as a 31* angle but in reality that is the grade but the angle would be around 17(ish)*.    It's not relevant to the discussion so nevermind.


a 31% grade is still steep as heck for a paved road intended for motor vehicles.. although I do think that section is closed to motor traffic, or at least appears so in the videos I've seen.
2009-10-20 9:14 AM
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Subject: RE: Elevation change per mile difficulty?
bryancd - 2009-10-20 6:43 AM
I agree they are more accurate, but not perfect. My SUUNTO when I switch between the GPS and altimeter, are often close, and then I use a mapping system or GOOGLE EARTH to provide a third data point. The alitimeter still tends to be the closest it seems.


It seems to me that if a device has two methods of measuring altitude it could be far more accurate by using both. A simple algorithm that makes logical sense would be to just average the climb measured from point A to Point B from the two devices.

Another huge advantage to having both in a device is that it could determine using GPS a period when the device isn't moving, then average up all the point elevations taken during that period, and use that elevation to calibrate the pressure altimeter. In mountaineering (before GPS) when navigation was critical you would calibrate the altimeter at every spot that had a known/accurate elevation based on a map.
2009-10-20 9:22 AM
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Subject: RE: Elevation change per mile difficulty?
MKAH - 2009-10-20 6:34 AM

blairrob - 2009-10-18 4:43 PM Mark, I mapped that route on Mapmyride.com and it came out to a little over 400 feet. Not sure how accurate it is though.

 http://www.mapmyride.com/route/us/ca/redding/287125590934475865


Rob,

When I mapped this route, I used plenty of data point fairly closes together.  This may account for the discrepancy between out elevations. 

Mark


Whenever using the BT Route Tracker you need to make sure you have a point at the bottom and top of every signficant climb. The BT-RT isn't smart enough to analyze the elevations between point A and B. It's easy for me because my climbs are long.

Mapmyride does consider elevations between points. I'm pretty certain that mapmyride filters out small climbs and that's why it always measures lower than BT which probably doesn't do any filtering.


2009-10-20 9:26 AM
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Subject: RE: Elevation change per mile difficulty?
That's a good point.
I had a friend last week tell me she went on a 16 mile run that had 3200 feet of climbing!! Here in AZ! I gently tried to tell her that was very unlikely unless she was running from Phantom Ranch up to Bright Angel Lodge at the Grand Canyon.
2009-10-20 9:37 AM
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Subject: RE: Elevation change per mile difficulty?
Laffenguy - 2009-10-19 4:46 PM
I did not know it had this much elevation. over 11,000 feet worth........wow. Now I almost feel super human.

Very impressive. You should feel super human!


It does take a long time to figure the routes though. But, now I know.

It does take time but it appears to me they've made some code changes to speed it up quite a lot.

****IF ANYBODY IMPORTANT IS READING****,
I'd go for the highest price membership in a hearbeat if that membership level allowed me to link up route segments either creating a new route in the RT, or during the logging of a ride (preferably both).
2009-10-20 9:42 AM
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Subject: RE: Elevation change per mile difficulty?
Bioteknik - 2009-10-20 10:07 AM
Pector55 - 2009-10-20 9:40 AM
gsmacleod - 2009-10-20 9:11 AM
Pector55 - 2009-10-20 10:05 AM

One question about road steepness.  I believe there is a definite difference in a road's stated "grade" versus the actual.  Someone help me out with this but basically, the incline is a rise over run calculation but it's often stated as the -1 TAN or something where 45* = 100%. 


Grade is simply rise/run; therefore an angle of 45* would give 100% as the rise and run would be the same.  You can also use trig for this but rise/run is the easiest.

Shane


Correct, as I stated it's just a rise over run calculation.  I now remember what I was thinking about.  I'm thinking about the angle in comparison to grade.  That is where a 45* angle yields a 100% grade.  I was thinking of it in terms of a claimed grade of 31* at Savageman.  It's easy to think of that as a 31* angle but in reality that is the grade but the angle would be around 17(ish)*.    It's not relevant to the discussion so nevermind.


a 31% grade is still steep as heck for a paved road intended for motor vehicles.. although I do think that section is closed to motor traffic, or at least appears so in the videos I've seen.


Most definitely!  I believe I read somewhere that there is a road in Pittsburgh which is 37% and one in Hawaii that is 45%!  They are all sick.  LOL
2009-10-20 11:12 AM
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Subject: RE: Elevation change per mile difficulty?
Pector55 - 2009-10-20 10:42 AM
Bioteknik - 2009-10-20 10:07 AM
Pector55 - 2009-10-20 9:40 AM
gsmacleod - 2009-10-20 9:11 AM
Pector55 - 2009-10-20 10:05 AM

One question about road steepness.  I believe there is a definite difference in a road's stated "grade" versus the actual.  Someone help me out with this but basically, the incline is a rise over run calculation but it's often stated as the -1 TAN or something where 45* = 100%. 


Grade is simply rise/run; therefore an angle of 45* would give 100% as the rise and run would be the same.  You can also use trig for this but rise/run is the easiest.

Shane


Correct, as I stated it's just a rise over run calculation.  I now remember what I was thinking about.  I'm thinking about the angle in comparison to grade.  That is where a 45* angle yields a 100% grade.  I was thinking of it in terms of a claimed grade of 31* at Savageman.  It's easy to think of that as a 31* angle but in reality that is the grade but the angle would be around 17(ish)*.    It's not relevant to the discussion so nevermind.


a 31% grade is still steep as heck for a paved road intended for motor vehicles.. although I do think that section is closed to motor traffic, or at least appears so in the videos I've seen.


Most definitely!  I believe I read somewhere that there is a road in Pittsburgh which is 37% and one in Hawaii that is 45%!  They are all sick.  LOL


I wish the USGS data had this climb's elevation.. looks about as close to a 100% grade as I'll ever see.
Of course this is a run though.. you can't bike up that nonsense. 

http://www.beginnertriathlete.com/discussion/training/map.asp?routeid=112155

BTRT says there's no elevation change!

Edited by Bioteknik 2009-10-20 11:18 AM




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2009-10-20 11:19 AM
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Subject: RE: Elevation change per mile difficulty?
Bioteknik - 2009-10-20 1:12 PM

I wish the USGS data had this climb's elevation.. looks about as close to a 100% grade as I'll ever see.

Of course this is a run though.. you can't bike up that nonsense. 


Last year when I was in Colorado Springs we hiked the incline; while it feels like 100% it maxes out at 68% and averages 40%.  It goes up about 2000' in around a mile and it took us about 30' to climb.

http://www.inclineclub.com/incline/

Shane


2009-10-20 1:10 PM
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Subject: RE: Elevation change per mile difficulty?
gsmacleod - 2009-10-20 2:49 PM
Laffenguy - 2009-10-19 7:46 PM



I would guess that the elevation gain is wrong; this would give about a 7% grade (assuming it wasn't point to point up a mountain) which would be incredibly challenging over the 45km you would be climbing.

I checked Mapmyride and it gives about 3700ft of total climbing which seems more reasonable.  Granted it still shows some 8% grades for about 1km and 5% for a couple of km's so still a pretty challenging ride.

Shane


It is a ride thru the Taunus mountains down the the Rhine river. I did re-figure like others said and kept getting around the same numbers. They did seem really high. I appreciate you took the time to re-figure it out.

Mapmyride is way easier to use, it auto figures for you based on route. Only took me 5 minutes to knock it out...............thanks for the link!!!
2009-10-21 8:52 AM
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Subject: RE: Elevation change per mile difficulty?
Laffenguy - 2009-10-20 12:10 PM

gsmacleod - 2009-10-20 2:49 PM
Laffenguy - 2009-10-19 7:46 PM



I would guess that the elevation gain is wrong; this would give about a 7% grade (assuming it wasn't point to point up a mountain) which would be incredibly challenging over the 45km you would be climbing.

I checked Mapmyride and it gives about 3700ft of total climbing which seems more reasonable.  Granted it still shows some 8% grades for about 1km and 5% for a couple of km's so still a pretty challenging ride.

Shane


It is a ride thru the Taunus mountains down the the Rhine river. I did re-figure like others said and kept getting around the same numbers. They did seem really high. I appreciate you took the time to re-figure it out.

Mapmyride is way easier to use, it auto figures for you based on route. Only took me 5 minutes to knock it out...............thanks for the link!!!


Before I replied, I pulled up your route, clicked "Reset Elevation" and got the same exact number you got. Because it was a point-to-point in a mountainous area, 11k climbing didn't look impossible.

I could get 14k in 55 miles by climbing up Mount Evans twice and hitching a ride down in a car both times. It stupid of course but (I think) that's the only way in Colorado that I could get that kind of vert in 55 miles except for doing a bunch of short hill repeats such as 67 reps up/down the hill up to my house (below). It would be 57.6 miles with 14,941' climbing (per BT-RT).
http://www.beginnertriathlete.com/discussion/training/map.asp?route...

Keep in mind that IMO mapmyride tends to generate climbing vert that's incorrectly low while BT-RT is probably high generally.

Eg. Savageman 56m bike (as I remember from the thread here).

BT-RT: ----------------------------> 6300'
Course designer who posted--> 5600'
Maymyride:-----------------------> 4300'

Edited by breckview 2009-10-21 8:53 AM
2009-10-21 8:54 AM
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Subject: RE: Elevation change per mile difficulty?
I've driven to the top of Mt. Evans.
2009-10-21 9:06 AM
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Subject: RE: Elevation change per mile difficulty?
gsmacleod - 2009-10-20 10:19 AM
Last year when I was in Colorado Springs we hiked the incline; while it feels like 100% it maxes out at 68% and averages 40%.  It goes up about 2000' in around a mile and it took us about 30' to climb.

http://www.inclineclub.com/incline/

Shane


On a sustained 45 degree pitch (100% slope) on loose talus/dirt you'd normally have to rope up. Most people would also feel the need to rope up on a solid smooth 45 degree surface.

Climbing 45 degrees on snow is the point where you feel like you should be roped but most climbers will wait until the pitch is 50+ depending on the exposure and the snow condition.

Standing at the top of a 45 degree pitch on skis is beyond "double black diamond" terrain which is usually 30-35 degrees. Unless the snow is super soft a 45 degree pitch is "one-fall" terrain meaning you will not be able to self-arrest a ski fall. By law, Colorado now rates this terrain as "Extreme" terrain.

Nobody could ride any bike up a 100% slope unless it was very short (like ten feet).
2009-10-21 9:19 AM
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Subject: RE: Elevation change per mile difficulty?
breckview - 2009-10-21 11:06 AM

On a sustained 45 degree pitch (100% slope) on loose talus/dirt you'd normally have to rope up. Most people would also feel the need to rope up on a solid smooth 45 degree surface.


Absolutely; just mentioned what it looked like

Have you been to the Incline?  It has railway ties as steps for most of the climb so it is more like climbing a staircase than hiking.  If you haven't ever gone up, I would say it is worth the trip is you make it down to Colorado Springs.

Shane



2009-10-21 9:22 AM
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Subject: RE: Elevation change per mile difficulty?
gsmacleod - 2009-10-21 10:19 AM
breckview - 2009-10-21 11:06 AM

On a sustained 45 degree pitch (100% slope) on loose talus/dirt you'd normally have to rope up. Most people would also feel the need to rope up on a solid smooth 45 degree surface.


Absolutely; just mentioned what it looked like

Have you been to the Incline?  It has railway ties as steps for most of the climb so it is more like climbing a staircase than hiking.  If you haven't ever gone up, I would say it is worth the trip is you make it down to Colorado Springs.

Shane



My parents live in the Springs... I might have to ask them about this. 
2009-10-21 10:05 AM
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Subject: RE: Elevation change per mile difficulty?
breckview - 2009-10-21 10:06 AM
gsmacleod - 2009-10-20 10:19 AM Last year when I was in Colorado Springs we hiked the incline; while it feels like 100% it maxes out at 68% and averages 40%.  It goes up about 2000' in around a mile and it took us about 30' to climb.

http://www.inclineclub.com/incline/

Shane
On a sustained 45 degree pitch (100% slope) on loose talus/dirt you'd normally have to rope up. Most people would also feel the need to rope up on a solid smooth 45 degree surface. Climbing 45 degrees on snow is the point where you feel like you should be roped but most climbers will wait until the pitch is 50+ depending on the exposure and the snow condition. Standing at the top of a 45 degree pitch on skis is beyond "double black diamond" terrain which is usually 30-35 degrees. Unless the snow is super soft a 45 degree pitch is "one-fall" terrain meaning you will not be able to self-arrest a ski fall. By law, Colorado now rates this terrain as "Extreme" terrain. Nobody could ride any bike up a 100% slope unless it was very short (like ten feet).


what kind of grade is the hike up to the lake chutes area on top of peak 8?  I did that last year and the wind was strong that day (like it usually is), but it almost felt like it would knock me off the mountain.

And yes, they do give us crazy mountain bikers close to 45% grades, but they're man made with lots of traction and they are very short.  I think IMBA solutions claims they can clear a 40% grade made properly. 

wow.. I'm quite a hijacker. 
2009-10-21 12:35 PM
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Subject: RE: Elevation change per mile difficulty?
Bioteknik - 2009-10-21 9:05 AM
what kind of grade is the hike up to the lake chutes area on top of peak 8? 

From memory I was going to say 20 degrees.

But, according to BT-RT it's 40.5% which is 22 degrees.
http://www.beginnertriathlete.com/discussion/training/map.asp?route...

Being able to accurately estimate pitches is important in ski mountaineering.

And yes, they do give us crazy mountain bikers close to 45% grades, ...

I assume you meant 45 DEGREES since that's what I said and to which you replied. If so, picture youself standing at the top of Lake Chutes and then trying to ride your mountain bike up from the bottom. Most all the lines in Lake Chutes are about 45 degrees.

If you did mean 45% it's about 24 degrees, and I have no idea if it's rideable.

Edited by breckview 2009-10-21 12:40 PM
2009-10-21 12:51 PM
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Subject: RE: Elevation change per mile difficulty?
breckview - 2009-10-21 1:35 PM
Bioteknik - 2009-10-21 9:05 AM what kind of grade is the hike up to the lake chutes area on top of peak 8? 
From memory I was going to say 20 degrees. But, according to BT-RT it's 40.5% which is 22 degrees. http://www.beginnertriathlete.com/discussion/training/map.asp?route... Being able to accurately estimate pitches is important in ski mountaineering.
And yes, they do give us crazy mountain bikers close to 45% grades, ...
I assume you meant 45 DEGREES since that's what I said and to which you replied. If so, picture youself standing at the top of Lake Chutes and then trying to ride your mountain bike up from the bottom. Most all the lines in Lake Chutes are about 45 degrees. If you did mean 45% it's about 24 degrees, and I have no idea if it's rideable.


yup, I did read the post wrong, it is 40% grade which they claim as rideable.  (using a man made ramp with traction added)

Edited by Bioteknik 2009-10-21 12:52 PM
2009-10-21 1:03 PM
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Subject: RE: Elevation change per mile difficulty?
Bioteknik - 2009-10-21 11:51 AM
  • .. it is 40% grade which they claim as rideable.  (using a man made ramp with traction added)


  • Here's a 17.6 degree (31%) trail segment (0.3 miles, 279 feet climbing) above the Sally Barber route that you rode while here. You probably saw it directly up the hill from the mine shaft equipment. I know people can ride it, but it's very tough. I honestly can't remember if I've ever made it non-stop.

    http://www.beginnertriathlete.com/discussion/training/map.asp?route...


    2009-10-21 1:42 PM
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    Subject: RE: Elevation change per mile difficulty?
    breckview - 2009-10-21 3:52 PM
    Laffenguy - 2009-10-20 12:10 PM
    gsmacleod - 2009-10-20 2:49 PM
    Laffenguy - 2009-10-19 7:46 PM





    Shane


    Before I replied, I pulled up your route, clicked "Reset Elevation" and got the same exact number you got. Because it was a point-to-point in a mountainous area, 11k climbing didn't look impossible. I could get 14k in 55 miles by climbing up Mount Evans twice and hitching a ride down in a car both times. It stupid of course but (I think) that's the only way in Colorado that I could get that kind of vert in 55 miles except for doing a bunch of short hill repeats such as 67 reps up/down the hill up to my house (below). It would be 57.6 miles with 14,941' climbing (per BT-RT). http://www.beginnertriathlete.com/discussion/training/map.asp?route... Keep in mind that IMO mapmyride tends to generate climbing vert that's incorrectly low while BT-RT is probably high generally. Eg. Savageman 56m bike (as I remember from the thread here). BT-RT: ----------------------------> 6300' Course designer who posted--> 5600' Maymyride:-----------------------> 4300'


    wow, there is alot of differences between the ones. never would think there was that much discrepancy. Here is the route for the HIM that was here, hence the reason to work hills. I rode the HIM route and did the other one to build longer hill climbing endurance. There is one part, right after the long climb, called the Hammer. There was as many people walking their bikes up the hill as riding them. Its short, but steep. Here is the link.

    http://www.ironman703.de/dokumente/english/hoehenprofil2008.pdf

    2009-10-21 8:22 PM
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    Subject: RE: Elevation change per mile difficulty?
    breckview - 2009-10-20 10:07 AM
    trinewby - 2009-10-19 7:07 PM Breckview,
    What problems have you seen with altimeters providing accurate elevation data?  They are far more accurate than non-WAAS GPS signals.

    Greg
    Barometric pressure, the weight of the air above you, is not static. When you're standing still and the elevation reported by a pressure-based altimeter changes, it just measured barometric pressure at a different level. But in order to measure elevation, the device must assume that pressure is static. By design, doing so is just an approximation. Computing "elevation" is pretty easy for any device because a small error usually isn't very important when taking a spot elevation. (Unless of course you're trying to navigate by comparing spot elevations to map features and a mistake has serious consequences which is common in mountaineering.) But when a device measures say 1950 feet and then 1970 feet, it has no idea if that 20 foot climb was real, if pressure just changed a bit, or if the mechanism it uses to measure pressure just isn't all that accurate. The device can either count the climbing as real which would result in an enormous amount of false climbing, or use an algorithm to filter it out. But any filter algorithm will also filter out real climbing as well.


    Yep, agree that barometric pressure is not static, but it doesn't change enough during a ride or a run to make any significant difference in the altitude reading it provides.  The only real practical problem is obtaining the current barometric pressure setting before your ride or run unless you know the elevation where you are located and can simply set the barometric pressure on the altimeter so that it reads that elevation.  My old Timex rubber watch with an altimeter function had that capability.  As far as accuracy is concerned, it was quite accurate.  I never expected it to be very accurate since it utilized a tiny electronic pressure sensor, but I checked it against the certified altimeter in my plane in flight and it was generally within 10'-20'.  It was sensitive enough to tell when I opened an air vent that slightly pressurized the cabin causing it to calculate a lower altitude.  I have also used it on commercial aircraft that typically pressurize the cabin to 8,000' when at cruise altitudes and it has been pretty spot on.  Of course, that assumes the pressurization system of the airliner is calibrated.

    Anyway, the point in bringing this up is that I believe an atmospheric pressure recording device will be capable of recording elevation changes far more accurately than non-WAAS GPS.  GPS is optimized for lateral navigation and is far, far more accurate on the x & y axes than the z axis.  But, you probably already knew that.  Like you said in another post, a device that had both GPS and altimetry would be the best of both worlds and I agree, but only if the GPS elevation isn't used.

    If you have the capability of pulling the elevation data from a database by plotting the GPS coordinates, that is the best way to determine the elevation changes and just ignore the GPS elevation calculations.  I have a track workout in my Garmin training center that I downloaded from my 30 a week or two ago and the elevation varies all over the place.  Needless to say, the track is flat as a pancake.

    Greg 
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