Interesting to read this book and THE BOOK OF MY LIFE by Teresa of Avila at the same time. They both describe four stages of meditation and the descriptions are pretty much the same. There are some differences of course: one is from a Tibetan Buddhist perspective and the other is from a Catholic one.

This book is meant for practiced runners who have experienced various levels of training cycles. It draws parallels between the mental tools and training patterns that we use in running and those same tools being used in a meditation context. Same tools, just applied in different ways.