This week, we explore the compensatory effects in total daily energy expenditure (TDEE) in relation to the amount of exercise performed.⁣

In other words, if you burn 1,000kcal through daily training, do you actually burn 1,000kcal more within that day?⁣

You would expect so, however humans are highly adaptive. Perhaps this stems back to certain ancestral compensatory mechanisms to preserve energy for survival?⁣

Careau et al (2021) used the largest database available measuring changes in TDEE in humans (n = 1,754) to answer this question.⁣

Their findings would suggest that a long-term increase in activity energy expenditure (AEE) does not directly translate into an increase in TDEE because. This is because other components of their metabolism will decrease to compensate and preserve energy.⁣

More specifically, the adults measured (non-athletes) had an average energy compensation of 28%, therefore only 72% of the calories burned during exercise translated to calories burnt that day.⁣

I.e. of the 1,000kcal burnt, 280kcal was compensated through a reduction in basal energy expenditure (BEE – immune, cardiovascular, kidney, brain, liver, digestive, respiratory, skeletal system etc.), and 720 additional calories were burnt that day.⁣

More interesting, the level of fat mass impacted the level of compensation, where individuals with higher fat mass experienced this to a greater extent. It was found that adults with a lower BMI compensated ~29% of activity calories, where those who were classed as obese compensated ~45% of activity calories.⁣

The theory would then suggest that as individuals gain more fat mass, it becomes increasingly harder for them to drop body fat as their energy compensation grows in strength.⁣

In addition, more restrictive calorie diets may further this compensation as there’s less resources and energy available for other bodily functions – therefore energy preservation becomes higher.⁣

Plus, we need to acknowledge the possible reduction in NEAT (non-exercise activity thermogenesis) which could be a large player in energy compensation.⁣

Knowing this, a once size fits all approach to nutrition programming simply doesn’t work. Therefore, more personalised approaches are needed to meet the fluid/compensatory demands of the individual.