Garmin Connect is using a different methodology to smooth elevation gain/loss compared to MotionBased. As a result, especially for Forerunner devices, the elevation gain/loss numbers will be inflated. We are still working on our smoothing algorithm and intend to run this across all activities at Garmin Connect in the future to more accurately reflect the actual gain/loss.
I believe I saw something about this earlier, it just seems odd that the site is powered by MotionBased but they're using a different algorithm that they admit is less accurate.
why "odd" when most of the features provided by motionbased are not available in connect!
I suspect that the motionbased were "better" especially on the FR series as they worked out and replaced the elevation at a certain GPS position using their own maps, when the "gravity" option was selected.
( there were problems when a cutting was made into a hill side to accommodate a 400m running track Their maps still showed the slope and hence a lap of the track was not flat!)
GPS only elevation (as on the FR305) is notoriously inaccurate.
