"There was a fencing master who never lost a duel. His
movements were so swift, his aim so true, and his skill so
astounding, that he was a source of amazement to all who beheld
him in action. However, his secret was simple. Before any duel or
engagement was entered into he, of course, would practice
faithfully for hours. In addition, he would fast from seven to ten
days." From Glorified Fasting
Also in this edition is "Fasting: Atomic Power with God"