Why is my activity's moving time different than my friend's?
- When recording cycling activities, Strava relies on GPS data to determine whether or not you are moving. A bad GPS connection could lead to false positives if your activity's GPS data tells Strava that you are moving when you aren't.
- Things like GPS drift, GPS signal loss or a 'jumpy' GPS track can also cause your activity to report more or less distance than you actually traveled. If for example, your bad GPS data tells Strava that you traveled a longer distance than your friend in the same amount of time you can expect different average speed calculations.
- When recording running activities, Strava uses your device's accelerometer to detect running motion. You can completely control your moving time when recording a run with the Strava mobile app by manually pausing the app whenever you want to rest. If you choose this option but are inconsistent, you might end up an inflated moving time.
Why is my activity's average speed on Strava different from my GPS device?
- When uploading rides Strava will use the recorded GPS data to calculate our own version of your moving time. During the upload process, whether you recorded with our mobile app or a third party device, Strava relies on a speed threshold to determine whether or not you are resting. Your device or platform may be using a different method than Strava when calculating your stats. For example, consider the process of determining how much resting vs moving time is in an activity. What constitutes a rest? Is it when you're at rest for 1, 3, 10, or 20 seconds? And what does your speed have to fall below in order for you to be considered at rest? 1 second might capture too many false positives and 20 seconds may be too strict. One calculation isn't necessarily correct or incorrect, but we do feel we're using standards that most athletes would agree upon.
- When uploading runs Strava relies on the recorded "timer time" which is the time the app or device was unpaused to determine moving time. As long as your device is recording conventional pauses, Strava will respect any pauses recorded in the file whether your device pauses automatically or you manually hit the pause button. It's important to keep in mind is that if you choose to pause you must do so consistently. If there are any pause events in your activity file our server will not remove any additional resting time. If you do not pause at all our server will calculate moving time based on the recorded GPS data. Again, even though elapsed time may be the same, Strava may calculate moving time differently than other platforms.
Why is my max speed so high?
Strava calculates your max speed in a such a way that a GPS error can cause the value to be greater than expected. To calculate max speed, Strava looks for the fastest speed recorded between any two GPS coordinates on your activity. If, for example, one GPS coordinate is recorded + or - 50ft from where you actually are, and the next GPS coordinate is also recorded + or - 50ft from where you actually are in the other direction, Strava will think you are moving faster than you really are because the distance between the two GPS coordinates isn't accurate. On the Analysis graph, there is a little bit of smoothing because we do not plot every data point but instead every 3 or so to make a readable graph. If you look at the analysis graph, you usually won't find the same max speed as is reported in the activity stats because the graph is smoothed.