Kundalini is taught to children as soon as they can walk, using the Shin'in Shinden sealing method. In this way, they learn to integrate this technique so completely into their subconscious that it functions as second nature by the time they become genin. The user repeatedly trains with this same method in order to improve their usage of this technique. The user must also strengthen their physiology in order to reach the higher levels expertise in the Kundalini.