total daily energy expenditure refers to the total number of calories a person burns in a day through various activities, including basal metabolic rate (BMR), physical movements, and digestion. Calculating TDEE involves considering BMR, daily activities, exercise, and the thermic effect of food. Understanding TDEE is crucial for managing weight, whether it's to maintain, lose, or gain weight. By knowing your TDEE, you can establish a suitable calorie intake for achieving specific fitness goals. It serves as a guideline to tailor diets and exercise regimens, ensuring they align with individual energy needs for a balanced and healthy lifestyle.