In recent decades, advancements in technology and use of technological devices have occurred at a rapid rate, thereby eliminating the need for physical activity, providing an environment conducive to prolonged periods of sitting, and encouraging fewer hours spent sleeping. In concert with the technological and lifestyle changes that have occurred over the years is an increase in many chronic diseases and serious health conditions such as obesity and type 2 diabetes. Although research has begun to elucidate the complex relationships between health and physical activity, sedentary behaviour, and sleep, many unanswered questions remain. Accordingly, this book sheds light on the relationships between health, physical activity (inclusive of light, moderate, and vigorous intensity physical activity), sedentary behaviour, and sleep in a high-risk population of inactive, abdominally obese adults. This topic should be particularly useful to health professionals and individuals trying to understand how the behaviours they participate in throughout the day influence their health, and to researchers interested in exploring the complex relationships between health and activity.