American College of Sports Medicine 
ACSM’s Metabolic Calculations Handbook [PDF ebook] 

This handbook provides a step-by-step approach to using metabolic equations, from basic math principles to applying the equations to an exercise plan. Chapters focus separately on each equation, provide an easy-to-follow process of solving, and demonstrate the varied uses of the equation in clinical as well as fitness settings. Each chapter includes a set of problems that focus on real-world applications of the equation. Step-by-step problem solution explanations are provided at the end of each chapter. A comprehensive exam at the end of the book tests the reader’s skill in using the equations.