Why Exercise is Essential emphasizes the importance of an active lifestyle and educates readers about the connection between physical activity and health.

The book begins with an explanation of exercise epidemiology and addresses the link between exercise, or lack thereof, and death. It also discusses the impact of other health conditions such as cardiovascular disease, obesity, diabetes, and cancer.

Why Exercise is Essential argues that a balanced exercise regimen comprised of cardiorespiratory, muscle strength, and flexibility training is the key to optimal health. The text acknowledges that change is difficult, but practical suggestions for reducing recidivism into a passive lifestyle are provided.

The appendices cover biometric goals and fitness testing. To help readers stay on the path to fitness, a list of resources supports real-life application of the information.