ID:1525258
 
What's the benefit of running like a ninja commonly portrayed in Naruto?
Weight loss.
http://www.youtube.com/ watch?feature=player_embedded&v=kWkPg5X2ZAY#t=98

1:38

http://www.wikihow.com/Run-Like-a-Ninja

4 and Tips

http://anime.stackexchange.com/questions/4221/ why-do-ninjas-run-with-their-hands-at-the-back

18 votes-iKlsR or 2 votes-Hazard

Based on all this I assume it's to bring momentum forward and to allow for an easier fox walk.