This title is directed primarily towards health care professionals outside of the United States. Designed to help readers understand and evaluate the relationship between exercise, immune function and infection risk, this book presents evidence for the "J-shaped" relationship between exercise load and infection risk. It also describes the components of the human immune system and key functions that protect the body from disease, the impact of acute and chronic psychological stress on immune function, and practical guidelines for minimizing the risk of immunodepression and infection in athletes. Further chapters explore different ways of measuring immune function, as well as the effects of heavy training on innate and specific (acquired) immunity, exercise in environmental extremes, and nutrition. Connections between exercise, infection risk, and immune function in special populations (elderly, obese, diabetic and HIV patients) are also addressed.