I knew about the theories and legends about samurai and ancient martial artists training themselves to sleep in very particular state of mind and body during war times. In a war mode, a warrior didn't sleep. I tried training myself and had done many times during “war times”… My training showed results.
About two days ago, this phenomenon happened to me again. I was sound asleep in my friend’s apartment on his couch. His brother room was right next to the couch I was sleeping on. His brother barged into the room in the middle of the night violently. I jumped up on the couch, still half-asleep but my body was in ready mode to fight. My brain was only working half; although my eyes were seeing, the information of where I was or who I was seeing was all in a waking stage. Only I saw a face of non-threatening confused expression, so I quickly tried to determine what’s going on in the situation. My brain quickly came to senses, and realized where I was, who he was, and everything right away. All these I described happened in about two seconds… I can laugh about it now, but I am really satisfied and amazed how my body was so strong right away waking up involuntarily into battle-ready state.
Ancient Samurai slept sitting with swords in their hands and they could engage in life-death battles right away with all the available strength (not waking up weak and sluggish) from the sleeping positions. I am getting there...