U can never outrun a bear
What u can do is stand up, open ur arms up high, make urself as big as possible and scream when u see a bear running toward u
If fail to scare it away fight it with all ur energy, fail lagi then curl up cover ur neck and wait for rescue/death lol
There is something like pepper spray u can buy in countries with common bear attack, u need to spray it just in time when the bear is running towards u to drive it away
Learn from I shouldnt be alive show