I've started running and an unexpected challenge is boredom. The running is challenging as is, but doing it for ~1h30m has been, for me, well, tedious. I guess that's a byproduct of always being within arm's reach of a phone.
You get more benefit from just walking, I believe.
Walking doesn't raise the heart rate enough.
https://www.ntnu.edu/cerg/personal-activity-intelligence#Bet...