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Mijn hardloop afstand klopt niet.

1136293
over 2 years ago

Vandaag een ronde van ongeveer 7,3 kilometer gelopen. Maar volgens mijn horloge was hij 8,2 kilometer. De snelheid die hij aan gaf onder het lopen klopte wel. Alleen het gemiddelde per kilometer was veel sneller. Waar kan dit aan liggen? Horloge heb ik al 2 jaar. Ik heb er nog nooit last van gehad

  • 0 over 2 years ago

    Most likely some GPS drift during the run. Zoom up the track on the map to the maximum, and inspect all the route and look for deviations. Or post a link to the activity here, so that we can look at it.

    Sharing a Garmin Connect Activity | Garmin Customer Support

  • 0 over 2 years ago in reply to 1136293

    Yes, indeed, the distance is wrong. If you export the GPX track, and read it with another tool, it gives indeed 7.3km. So no GPS drift resulting in a wrong track - the track is perfectly all right.

    This is because of a stupid algorithm used by Garmin for replacing the trigonometric distance between two GPS points, in case of short GSP signal dropout, by the distance calculated with the help of the cadence, and an adjusted average stride length - in the same way as it is done on a treadmill, and at indoor running.

    I suggest sending the links to the Support, but I am little bit afraid that they still do not understand that their algorithm for pace and distance at a GPS dropout is completely wrong, because similar cases are quite common since years, and especially noticeable in case of frequent brief GPS drop-outs, like in a dense urban environment, under dense vegetation, or at open water swimming.

    The Support will tell you that you must wait till the watch learns more about your running, calibrating the stride length. That's partially true, but still the algorithm employing the calibrated pace is completely wrong - it adjusts the pace, using the cadence data from the accelerometer (increasing the pace at high cadence, and vice versa), and calculates the distance from it, completely ignoring the GPS data of the two delimiting points.

    Let's say, the watch loses the GPS signal at point P0, and recaptures it in the next second at P1 with the distance of 1m from P0, it will not use this trigonometrical distance, but instead it will switch to the indoor mode, and use the calibrated stride length and cadence. The resulting distance can be from 0 to several meters (depending on how fast your arm just moved), completely ignoring whether it is physically possible or not. It is sad, but I am afraid Garmin's engineers do not want to recognize the method is completely wrong.