Strava followup

I emailed Strava's customer support asking what the accuracy of a segment that short would be. Here's their response. The accuracy of very short segments depends entirely on the quality of the GPS hardware recording the data; however I can say that the shorter the segment, the more prone it will be to GPS errors. Most GPS devices have sampling rates anywhere from every 1 second to every 10 seconds. Clearly a ten second sampling rate is going to render a 5-second-long segment completely inoperable. Unfortunately there isn't really anything that can be done to improve the accuracy of the segment - other than encouraging your friends to get high quality GPS devices. I did some experimenting in a field during barrier practice where i set a lap marker on my garmin before and then after the barriers i set up. I had the auto lap feature but it was a total crap shoot as to when it would trigger a new lap. It was a difference of up to 20 feet. So long story short it might not be that reliable.