Just a quick thought
Put your ego in harm's way. Be in a position where failure is possible but without accepting that as the final position. Be open to the suggestion that what you thought was your limit isn't - even though it does a more than passable impression of it! The growth, the actual development occurs at those outer limits of comfort. Well, in the rest periods afterwards in truth. You take yourself to your limits and stay there for a while, occasionally darting out and returning quickly - like a child at the edge of a pool of darkness, nudging into the gloom and jumping back, heart pumping fast enough to burst out of your chest. Having established that you can make it that far, you go a little further the next time. You take your body out into the dark, introducing it to what you require. Introductions over, you relax and your body, newly aware of expectations sets about readjusting itself, hypercompensating to accommodate new expectations. Until you get comfortable with not being comfor