And you are of course in the Arctic...you are running, and that bear is closing in fast. You come near some ice flows. Do you:
A) jump in the water and proceed to swim towards a chunk of ice, knowing that if you do, hypothermia will set in and the polar bear can swim to that chunk of ice.
B) turn around and start yelling and waving your hands. Even taking off yuour jacket and waving it around. Thus, killing the bear's prey/chase drive and confusing it...and move around...you are more maneuverable, but not quicker than the bear. This is what dogs do to bears...
C) pee/defecate in your pants in fear (hey, it may deter him)
D) there is no fighting a Polar Bear...