You don't know if you trained for an hour or 90 minutes. All this may sound like you are being picked on, but from an instructor's point of view the half hearted trainer annoys me. Train or don't train, but the ones who say, "I'll see you in class on Monday", then never turn up waste everyone's time. There are no secrets in the martial arts. It's there for everyone who wants it. You just have to go and get it.