Power Baseball by Coop DeRenne and Tom House is a comprehensive study on weight training, weighted implement training and cross-specificity training.
It lays out a complete training regimen for both pitching and hitting. It goes into specific exercise, overload/underload specifics and programs for both. This book, in our opinion, is one of the best books on the market for anyone interested in improving their throwing velocity and/or batspeed.
"This research text specifically provides the player, coach and parent with the historical evolution of our weighted implement training scientific field. This new weight training concept is based on the principle of "Specificity of Training." This principle states, in general, that any sport-skill is specific in nature with its own inherent competitive range of motion and rate of speed. Therefore, the athlete while training in the weight room must exercise the specific sport-skill in question (e.g., hitting and throwing)precisely by duplicating as close as possible the skill's competitive rate and range of motion.
We will provide the pitcher and the hitter with research proven weight training information that will help maximize their skill performances.... Our Weighted Implement Training Programs for the pitcher and hitter supplements our specific year-round weight training program by using precision heavy and light overload/underloaded implements (bats and baseballs) to explosively train pitchers and hitters."
As you can see this is a MUST read for all serious players.