Steven Kotler: The Rise of Superman, Decoding the Science of Ultimate Human Performance
The Flow is rare for ordinary humans, but for extreme athletes it is mandatory and everyday experience. It is the state needed to reach our limits.
Daniel Goleman, Cary Cherniss: Optimal
Optimal from Goleman and Cherniss is a book on how to extend "the flow" moment in optimal state that gives us sustained excellence every day.