I feel like that definition isn't quite accurate. The person ATTEMPTS to run very fast. They are usually not all that successful on account of this being reality and not fictional ninja-physics
There's people who claimed that, but every study I've seen indicates the opposite, largely due to the fact that swinging your arms and moving your body helps add momentum while you run, making it easier for your legs to propel you forward.
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The naruto/anime run is literally just to make animation easier
I have no idea why I have to explain this, but not only is the naruto-run not more effective, it's possibly the dumbest fucking pose one can do while actually still being able to run. Ever seen a dude naruto-run and trip? I have. It's fucking hilarious. It's not like a normal dude running and tripping; it's a fucking full-metal face-plant.
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The naruto/anime run is literally just to make animation easier