Using galaxy watch 4 classic using the built in running tracker:
1. Samsung health app logged 4.72km, 34:29
2. Auto synch with Strava logged 5.08km, 33:16
3. Samsung health GPX export, imported into Strava 5.08km, 33:34
4. Samsung health GPX export, imported into MapMyRun 5.09km, 35:29
What the heck is going on?? The data is wildly inconsistent.