Dr. Moshe Feldenkrais
The most influential figure on the development of Krav-Maga is probably Dr. Moshe Feldenkrais (1904-1984) who in the 1920’s discovered the phenomena of the ‘unconscious reaction’ (later known as reflexive or spontaneous reaction). The Haganah command, detected the potential and granted Feldenkrais a three years budget to train its members. Following this experience, at age 26, Feldenkrais published a book named ‘Ju-Jitsu and Self Defense’. This book was the outcome of his insights and experience in hand-to-hand combat, and, his discovery of the ‘unconscious reaction’ .Feldenkrais book and concept, laid the foundation for an improved fighting regimen and better training methods. In his book, we can note elements such as the simultaneous block and attack, nose-bridge use and, release from front and rear chokes, which were later identified with Krav-Maga.
Source: Israel Martial Arts