Ninja Run Nanruto

Ninjas in Naruto run with their hands at the back (which is very different from normal anime character running).
Why is that? Is it because of their too much running speed or the wind force that their arms tend to be at their backs?
Actually there is history behind this.
Back in the age of the Samurai and Ninjas.The reason is because Kimono's have very large sleeves and catches wind like a damn parachute.
That is the reason for running behind with their arms behind their back. To reduce drag.
Japan is all about preserving history, so that's why you still see it being shown in media today in japan.
Don't complain that a game is hard if your playing on hard mode.....thats just silly.
Don't they lose balance when they run like that? Is there any explanation for this?