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Attackpoint - performance and training tools for orienteering athletes

Discussion: 13% grade?

in: Charlie; Charlie > 2017-07-18

Jul 19, 2017 2:48 AM # 
260m climb in just 2.55 miles, and that's taking it easy? I'm realising how flat my part of Colorado is by comparison.
Jul 19, 2017 8:34 AM # 
The garmin is pretty shaky on climb. It has shown as little as 200 for the same route, but it is pretty steep around here. That's why I rarely ride my bike from home.
Jul 19, 2017 12:44 PM # 
GPS is pretty bad on elevation, but when you upload to Attackpoint, it doesn't use the GPS climb. Instead, it takes your route and looks at a digital topo map to figure out the climb. But that's only going to be as good as the route. If you look at this particular route, it appears that the location fix wasn't very good for part of the time, because we'll assume you weren't wandering in the woods. Depending on how it's off, that can produce more (or less) climb, e.g. if you were walking along the top of a cliff and your route was off, Attackpoint might think you were repeatedly going up and down the cliff.
Jul 19, 2017 12:51 PM # 
We did some hikes along steep river valleys in northern Oregon and the GPS signal had us jumping up and down those steep hillsides though the trail was mostly level. Reported climb was thus well-exaggerated, so it's only as good as your track, which can be off.

Charlie's driveway is a workout in itself!
Jul 19, 2017 1:11 PM # 
If you just do it the old-fashioned way, counting contours, you get about 550 feet, or 1,100 total elevation change. Over 2.5 miles that gives an average grade of a little over 8%. Sounds about right.

(RideWithGPS is another piece of software that struggles with this. I put in Charlie's route, leaving out his driveway. The elevation profile is very simple -- down 100', up 100', down 200', up 200', down 100', up 100'. So 400' climb, plus a couple of extras 10s or 20s if you wish. Their number for climb is 323'. It also doesn't pass the common sense test.)
Jul 19, 2017 1:29 PM # 
I didn't realize that AP calculated climb that way, which is useful. (I had wondered whether something did that.) I've been replacing the climb from my GPS tracking with info from contours. Having AP do it from a GPS track would be easier, and probably good enough for tracking how much climb I do each week. I didn't even notice that I could see the uploaded track until you mentioned that.
Jul 19, 2017 1:50 PM # 
It's only as good as the DEM, of course. In Manitoba, it thought the ground was essentialy flat, and the climb numbers are way low.
Jul 19, 2017 4:00 PM # 
Naturally. But for around where I live, it may be adequate for most hikes, and maybe some mapping. Perhaps easier than a lot of contour counting.
Jul 19, 2017 4:55 PM # 
Good about Rhonda. Wish her well.

This discussion thread is closed.