I go back and forth. The space I have is very limited. I can only take about 9 steps before I reach the kitchen wall. Once I hit it I turn left and walk 9 steps until hitting the bedroom wall, then I turn right and walk towards the kitchen wall again. I've been doing this for years.
I read a wiki article once many years ago about this POW who walked in circles inside his cell and managed to reproduce in numbers of steps a trip across of Western Europe on foot or something like that. I simply cannot find that article anymore, I think it was a German guy.