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How to calculate total ascent


KevinG
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I use a Garmin 310xt and download my data to Training center and Garmin Connect. How do these programs work out the total ascent? I did 7weekspoort and the ascent on the website is 1276, training center worked it out as 1344 and garmin connect worked it out as 1975. I have found these discrepancies often. Which is accurate?

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Your Garmin probably uses barometric pressure to measure change in altitude. The calculation is distorted by the sampling rate (ie every 10s, 30s etc), and other causes of change in pressure, weather system moving across which results in increase or decrease in pressure to the whole area, change in temperature which also results in change in pressure.

 

I get an ascent and descent (normally quite different) in a spinning class on my Suunto. I did 3000m of ascent and descent at the BSG Energade this last weekend. The swimming really screws up the altitude readings.

 

Rather rely on something which uses maps as its calculation base.

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Train for 1975 and hope to ride 1276.

 

There will always be differences but if you train and ride to the same figure you will know how it feels.

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The answer is simple. Different software sees Gradient Differently. Here goes a short explaination.

 

The 1 application will see anything above 4% gradient as an "Ascent", and hence, anything below 4% as "FLAT", and the same would apply to descent (above -4%), and anything below as "FLAT" (0-> -4%).

 

The second application might see that gradient threshold at 2%, hence the Different Total Ascent

 

The Third application might read any increase in Altitude (as per GPS) as an Ascent, and Vice Versa for the Descent

 

I hope this explaination is kinda Clear. But thats how I fugured it. In fact some apps actually tell you what their gradient threshold is for Ascent/Descent.

 

Try SportsTracks3 it's compatible with the Garmin Devices, and it's free.

 

Good Luck

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On Garmin connect you can enable elevation correction - the setting is below the unit silhouette - you will see elevation correction (Enable) or (Disable). Click enable and it should correct it to the actual elevation gain.

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But would you not prefer an ascent to be above a certain gradient threshold? Just a thought, because if you have a rise of 2m, and you do this about 50 times during your ride, your total ascent would be 100m, which would be inaccurate, because the ride would essentially be flat, RIGHT?

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But would you not prefer an ascent to be above a certain gradient threshold? Just a thought, because if you have a rise of 2m, and you do this about 50 times during your ride, your total ascent would be 100m, which would be inaccurate, because the ride would essentially be flat, RIGHT?

 

Well I use my Edge 800 and it seems to be inaccurate, sometimes more than others.

 

Well, if you climb 2m 50 times over the distance of your ride, then you have effectively climbed 100m total on your ride = not flat. If you are doing a loop, you would also have a 2m descent on that loop too, which would be noted.

 

If you want to see what climbing you have done on a certain hill, just point to the base of the hill on the elevation graph, and check the elevation and distance reading, and then the top and check the elevation and distance reading, and then you can work out the gradient from that.

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