When the military was training for war they took it very seriously. All males were trained from such a young age till when they aren't capable of fighting.  They were tought to learn to master weapins and tactics. The youth also accompanied the Aztec army while fighting to comprehend what would happen in certain situations. However, they were only aloud to stay in the back. When men started to fight in war they were able to cut of their pony tail that they had been growing                                             since they were born.