RecruitingBehavioural interventionThe Effects of an Obesogenic Lifestyle in Recreationally Active, Young AdultsThis clinical trial aims to learn about the alterations in insulin resistance and metabolic flexibility following a transition to an obesogenic lifestyle in fit young men and women. The main questions it aims to answer are: 1. Does adding excess carbohydrates when transitioning to a sedentary lifestyle promote insulin resistance and impaired 24hr glucose regulation in healthy men and women? 2. Does adding excess carbohydrates when transitioning to a sedentary lifestyle lower the body's ability to break down fats and carbohydrates in healthy men and women? 3. Does the added physical activity blunt shifts in carbohydrate and fat oxidation in healthy men and women?