In modern ninja movies, swords are carried behind the back, with the hilt up, while it sticks out over the right shoulder, and the tip of the scabbard sticks out at the left side. Everyone is already so used to this position of the sword that they do not question this method of carrying. Japanese expert in the field of Japanese weapons Nava Yumio conducted several experiments, as a result of which he came to the conclusion that the ninja never carried a sword as shown in the movie.

Here are the arguments given by Nava Yumio:

Sticking out on one side of the handle and on the other side of the tip of the scabbard will cling to branches, trees and other obstacles, creating unnecessary noise and drawing attention to the ninja warrior;

If the sword is stuck behind your back, it will not allow you to do somersaults and rolls, which are constantly used by the ninja in battle. If you try to make a roll with a sword on your back, a square guard with a high probability can cause a facial injury;

A sword placed in this way is almost impossible to put back into the scabbard;

A long sword from such a position is almost impossible to snatch, especially given the body structure of the Japanese, and especially the ninja, who even among the Japanese stood out for their subtlety.

Given all of the above, the Japanese expert concluded that the ninja wore their swords on their left side. It is from this position that you can quickly and effectively remove the sword, together with the extraction of striking.