There are some great books written about flow, the altered state where you can reach peak performance.
Have you already read them?
A classic one is Flow: The Psychology of Optimal Experience by Psychologist Mihaly Csikszentmihalyi. Original published in 1990. A ‘must’ read!
More recent the book The Rise of Superman by Steven Kolter is published. This books gives a lot of insights in Flow states of extreme sporters. Very interesting for every ‘normal’ man of woman as well.
Very recently a Dutch Hockey Coach which won Olympic gold with his team, wrote a great book about Teamflow. The book ‘Flow van Goed naar Goud’ (Flow from good to gold) is available in Dutch only at the moment.
Another interesting book is Bold, by Peter Diamandis and Steven Kotler. This book is about abundance and exponential technologies. In one chapter about innovation they describe some very interesting things about flow in organisations.