Issues with Moving Time and Speed (pace) When adding timestamps to tracks

[fulmar2]

Today I added a feature where the user could interpolate (add trackpoints). This feature will really help out people who are trying to re-create activities with the Add Timestamp tool. Previously, if a user tried to add timestamps to a track that had very few trackpoints, Strava would interpret these large gaps in time stamps as stopped time. This would mess up the average pace, and it would make the speed graph look eratic. This is a bug with how Strava interprets tracks - but by adding in extra points, it seems to work-around the Strava behavior.

[40°]

This option works perfectly. There are absolutely no problems with the Country right now. Thanks.

[fulmar2]

I wanted to provide an example of the difference between using / not using the "Interpolate Points" option when you're adding Time Stamps to your files:

The Interpolate Points option is found on the 2nd page that you come to; the one after you upload your tracks to the tool:

Interpolate Points will make one point every second. Most hand-drawn tracks have the points very far apart, which leads to poor smoothing of the track.

If you hand-draw a track, sometimes the points will be very far apart. This makes for a smaller file, but a problem arises when calculating pace between each point. Since each point is far apart, you can experience drastic changes in pace between each point which leads to erratic pace / speed in your final Strava File IF you have selected the "Consider Elevation When Calculating Speed" option. Here is an example of a highly-spaced file being timestamped WITHOUT interpolation:

A timestamped file WITHOUT interpolation. Notice how the blue line (pace) is very erratic. I used the run-pace setting when time-stamping this file.

If I take the exact same file as before, and also apply the "Consider Elevation When Calculating Speed" option, and then I select the "Interpolate Points" option as suggested above, this is what the speed profile looks like:

Speed profile (blue line) when using the "Interpolate Points" as well as "Consider Elevation When Calculating Speed" option. (Run option selected).

Note that the calculation will only be as accurate as the elevation values in the file you provide. Therefore, if the file you upload has erratic elevations, you could see some erratic changes in your pace. The tool only uses elevation that you provide in the file. If your file does not have any elevation, the tool is unable to calculate your pace based on elevation. At this time, my tool does NOT use DEM (Digital Elevation Models) to look up elevations.

[40°]

Thank you for the helpful information.