I walk, take a bus or train, then restart to walk. I would like Strava to calculate only the part where I walk but I didn’t find a solution except start-finish and then start-finish a second time. And then add the 2 distances, the 2 times,… and how can I handle the average bmp and the rest? 
I tried using Pause during my bus/train use, but Strava still considers that I walked during the Pause and add the m or km to the total. I don’t want that!