Total daily energy expenditure (TDEE)

Total daily energy expenditure (TDEE) is all the energy a client uses in a day through basal metabolism, physical activity and the thermic effect of food.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 464.} Activity, environment, caffeine and sleep can change it from one day to the next.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 464.} Some authors divide activity into exercise and non-exercise activity thermogenesis (NEAT).^{2Norton and Baxter, The Complete Reverse Dieting Guide, p. 14.}

IPTA puts basal metabolism at 50 to 65% of TDEE, physical activity at 30 to 50% and the thermic effect of food at about 10%.^{3International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 465.} Physical activity is the most variable component.^{3International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 465.} The NSCA gives a higher range for resting metabolism, about 60 to 75% for most people.^{4Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 121.}

In practice

• When a client’s weight is stable, current intake roughly equals expenditure; the NSCA recommends an accurate three-day food log to estimate it.^{5Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 123.}
• Multiplying an estimated basal metabolic rate (BMR) by an activity factor gives a starting point, but every method is still a rough estimate.^{6International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 466.},^{5Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 123.}
• Structured exercise and everyday movement raise TDEE; a higher-protein diet adds a little, and gaining lean mass may raise BMR.^{6International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 466.}
• During a diet, a lighter body costs less to move and metabolic adaptation lowers expenditure further, so a calorie deficit eventually becomes maintenance.^{7Norton and Baxter, The Complete Reverse Dieting Guide, p. 13.}