Sink or Swim; or, Harry Raymond's Resolve Jr. — Horatio Alger Jr.

It's very rare that a book can mean so much for professional sporting; Prof. Dr. Jan Olbrecht's book does! - He has a Ph. D. in physiology and biomechanics and is training adviser to numerous world class athletes - His method is based upon careful planning and a unique method of lactate testing to assess and optimize the athlete's conditioning and potential - His book should be considered as a manual for the modern coach who wants to know before planning and periodizing what kind of conditioning adaptations he may expect - It provides knowledge and shares experience in a very understandable and applicable to every training situation - It advances some new important concepts, most notably that training at anaerobic threshold speeds is not the most effective way to improve aerobic endurance and that aerobic and anaerobic metabolism must be developed to optimum, not maximum, levels in order to perform well in competition.
(Based on refined outcomes following a re-analysis of the characteristics of anaerobic capacity exercises, some changes have been made regarding their description for long distance swimmers in comparison with previous publications (see Classification of Training Exercises).

There is also an app available:

https://play.google.com/store/apps/details?id=com.fgpartners.thescienceofwinning