When it comes to losing weight, the general assumption has always been to go on a diet and start exercising. Perhaps easier said than done, the general idea is straightforward. However, a new theory has complicated things: the constrained total energy model.
This new model suggests that when you increase your activity levels, your metabolism will compensate, blunting total calories burned. This theory has led to numerous pop-science articles with headlines that suggest exercise isn’t a good strategy for losing weight.
Is this true?
This article looks at the constrained energy model, as it’s crucial to understand the effect that activity has on your health.
Key Points You Need To Know!
The constrained energy model is an alternate theory for energy expenditure that suggests increased activity and calories burned are not linear, as once thought.
Studies show that this can occur, but at the higher ends of activity levels, and is not complete compensation.
Energy compensation is not a concern for the vast majority of the population.
These same studies show that resistance training can actually increase energy expenditure more than predicted.
Some have grossly exaggerated findings to suggest that exercise is all but useless for losing weight.
How Does Exercise Help Lose Weight?
Exercise provides numerous benefits for weight loss, but this article will concentrate on the extra calories burned. This energy expenditure is one part of your overall Total Daily Energy Expenditure (TDEE or TEE).
TDEE is made up of four main components:
Basal metabolism/BMR (~60–70%)– Energy required for basic life functions: breathing, circulation, organ function, and cellular maintenance.
Physical activity (~5–15%)– Structured exercise like lifting, running, or sports.
Non-exercise activity/NEAT (~10–20%) – Everyday movement such as walking, posture, fidgeting, and chores.
Thermic effect of food/TEF (~5–10%)– Energy used to digest, absorb, and process nutrients.
Your TDEE is then compared with your total calorie intake to dictate your weight.
Calorie Intake > TDEE = Weight Gain
Calorie Intake < TDEE = Weight Loss
Calorie Intake = TDEE = Weight Maintenance
Of these, activity is the most modifiable part of TDEE, making it an important tool in weight loss.
Additive Vs. Constrained Total Energy Expenditure Model
There are two models that attempt to explain what happens to the calories burned during exercise and activity:
Additive Total Energy Expenditure Model– Calories from activity have a direct impact on TEE.
Constrained Total Energy Expenditure Model– Total calories burned are kept within a narrow range.
What Is The Additive Total Energy Expenditure Model?
The additive model is the basic model we’ve always used for weight management.
Calories from increased activity are added directly to your TDEE. 500 calories burned on a run increases your TDEE by roughly 500 calories.
BMR (1300) + TEF (200) + NEAT (500) + Exercise (500) = TDEE (2,500 calories)
Keep in mind that the additive model does not preach that energy expenditure is perfectly linear.
What Is The Constrained Total Energy Expenditure Model?
The constrained model is a new theory that suggests that when activity increases, the body compensates by reducing energy expenditure elsewhere.
For example, on your 500-calorie run, your BMR may decrease by 200-300 calories, resulting in just a 200-300 calorie difference.
BMR (1300) + TEF (200) + NEAT (500) + Exercise (500) – Adaptation (300) = TDEE (2,200 calories)
Exercise still raises TDEE, but not nearly as much as we once thought.
Is There Evidence For The Constrained TEE Model?
This theory is largely pushed by a Duke University Professor, Herman Pontzer. Over several years of research among hunter-gatherer tribes, he conducted a study published in 2016.
Compared the activity levels, energy expenditure, and body composition of 5 different populations
Instead of a linear relationship, the relationship plateaued over the upper range of CPM/d, roughly 30% of the dataset.
This equated to 230 CPM/d
These results have led to a slew of pop-science articles claiming;
The exercise paradox: why workouts aren’t great for weight loss but useful for maintaining a healthy body weight (The Conversation, 2025)
Why exercise isn’t much help if you are trying to lose weight (New Scientist, 2026)
You’re not burning as many calories as you think you are with exercise — here’s why (New York Post, 2026)
However, it’s important to point out;
1. The study states energy expenditure plateaus occurred in the upper ~30% of participants. However, it uses CPM/d, which is difficult to translate into real-world activity because CPM is a device-specific accelerometer metric.
2. Any compensation that might occur seems to occur with aerobic exercise. In an interview with New Scientist, it is stated that energy expenditure tends to be higher than expected with resistance training.
3. His study research doesn’t suggest all energy is compensated for, as many articles seem to suggest. Rather, the model hypothesizes an increase to a threshold, followed by a gradual increase in compensation.
While there is a pre-print for a new study in 2026, a full copy is currently unavailable, making it difficult to analyze in full.
Evidence Against The Constrained Total Energy Expenditure Model
Now, let’s look at some evidence and research that contradicts the constrained TEE model.
Levels Of Compensation Have Always Been Acknowledged
While there is no evidence, compensation has always been assumed on some level. The best example is with metabolic adaptation during prolonged periods of caloric restriction.
Research shows that a prolonged diet can cause your BMR to drop. For this reason, intermittent calorie restriction has shown to minimize metabolic adaptation while maintaining fat loss, or even slightly increasing it.
Therefore, the idea that metabolism will adapt is not necessarily new. It’s interesting to note that this concept has also been used by pop science to claim that diets don’t work for fat loss either.
The Additive TEE Model Has A Very Long History
The framework underlying the additive model dates back to the late 1800s and early 1900s. Since then, it has demonstrated predictive utility across controlled metabolic ward studies, athlete fueling strategies, and clinical weight-loss interventions.
Late 1800s — Wilbur Olin Atwater
Built human respiration calorimeters.
Measured heat production in humans.
Developed the Atwater factors (4 kcal/g protein, 4 carb, 9 fat).
Applied thermodynamics to human metabolism experimentally.
This shows that the human body obeys the law of conservation of energy.
1918 — Lulu Hunt Peters
Published Diet & Health: With Key to the Calories.
Popularized calorie counting for the general public.
Turned lab calorimetry into behavioral dieting arithmetic.
This is arguably the birth of public-facing calorie tracking.
1919 — James Arthur Harris & Francis Gano Benedict
Developed the Harris–Benedict equation.
The first widely used predictive formula for basal metabolic rate (BMR).
Anchored energy expenditure estimation mathematically.
Of course, things are always changing, and time established doesn’t prove it’s true.
The difference is that this model has had practical implications with the population for fat loss. This framework has been the backbone of dieticians’ work for decades.
Examples in the Real World
While not “scientific”, the constrained model would need to explain how people have been losing weight for the past century. Specifically, they have been using additive-model-based formulas and even predict weight loss.
At the same time, we can look at endurance athletes. Michael Phelps famously reported he ate 6,000 calories a day during training. This is seen in all endurance athletes; however, they don’t gain fat.
In fact, athletes and nutritionists can accurately predict the calories they need based on activity levels. People who have simply added walking to their daily routine have lost weight.
Research Against The Constrained Total Energy Expenditure Model
Gonzalez et al. (2023) conducted a large review of the literature on energy use and the constrained energy model. While nuanced, they concluded that adaptation likely occurs but is only an issue for those with high levels of activity.
“An upper limit of TEE probably exists, but this is likely irrelevant for most people… even if some constraint exists, it is unlikely to fully offset physical activity, such that further increases in physical activity will result in a net increase in energy expenditure, just not in a linear manner.”
Perhaps the best applicable study on this was performed by Thurber et al. (2019). This research team measured metabolic information from runners participating in a 14-20 week ultra marathon, Race Across the USA.
During Week 1, the runners’ predicted energy expenditure matched their actual expenditure at around 6,200 total calories.
By Week 20, their predicted and actual energy expenditure did not match. After adjusting for various factors, the runner’s energy expenditure was 596 calories lower than expected!
This is interesting, but we need to consider some key nuances:
1. These athletes were running 250 km/week (155 miles) for 20 weeks. This is equivalent to 6 marathons per week for almost 5 months.
2. Even under extreme sustained activity, compensation reduced predicted expenditure by ~20%, but total daily energy expenditure remained dramatically elevated. It’s not a complete adaptation. Further, these are extremely high levels of activity.
3. A 20% drop is still a much smaller adaptation than suggested with the constrained model.
4. As elite runners, it’s safe to assume they had been running high mileage for many years. However, during Week 1, their actual energy expenditure was only 2% lower than their predicted energy expenditure. This suggests the drop likely occurred due to extreme volume over consecutive days for 20 weeks, rather than a permanent adaptation.
5. This is the longest event to track metabolic measures. In other words, this is as extreme as it gets.
Does Increasing Activity Burn More Calories Or Just Get Compensated?
As we saw above, the main argument concerns how many calories your body burns from increased activity.
Do those calories directly add to your total energy expenditure?
Will other systems adapt, blunting total energy expenditure?
Like every other function in our body, it’s not a simple yes or no answer. There will be a spectrum depending on several variables:
1. How much activity are you doing? If compensation occurs, it is much more likely when activity levels are high.
2. What type of exercise are you doing? If compensation occurs, it’s more likely to do so with endurance training than with strength training.
3. How big a caloric deficit are you in? We do know that metabolic adaptation can occur to some degree during prolonged, higher caloric deficits.
4. What is your base level of activity? If compensation occurs, it’s more likely to occur in advanced athletes who already have high levels of activity. On the contrary, going from sedentary to walking 30 minutes a day isn’t going to be of any risk.
Does Exercise Help With Weight Loss?
Yes. We have numerous articles specifically on this. This includes studies showing;
Exercise alone can be superior to diet alone (Clark, 2015).
Exercise + Diet is superior to Diet alone for weight loss (Clark, 2015; Wu et al., 2009).
Exercise + Diet is superior to Diet alone for long-term adherence (Wu et al., 2009).
At the same time, the benefits of exercise move far beyond calories burned, including;
Increasing your RMR (metabolism)
Improving glucose metabolism
Improving hormones
Increasing executive function (can help with dieting)
Mitigating muscle loss (weight training)
LINK Check out these articles for a more in-depth explanation!
Final Say: The Primary Problem With The Constrained Model
The primary problem with the constrained model comes not from the actual theory but the way it’s presented to the public. As seen with those headlines, it’s presented to the public as “exercise doesn’t actually work for fat loss”. We believe that presenting health information to the general public should be done more carefully and with nuance.
Only 25% of the population meets basic physical activity levels, and sedentary levels are at an all-time high. This messaging doesn’t even apply to the vast majority of the population, as they will definitely benefit from exercise. At the same time, this doesn’t even apply to resistance training, yet this is casually ignored.
For this reason, we always promote increasing cardio, general activity, and a proper progressive training program for fat loss.
Please go check out our programs here and give us a shout if you need any help!
FAQ: Additive TEE Model Vs. Constrained TEE Model
1. Does the Constrained Energy Model mean exercise doesn’t help with weight loss?
No. The constrained model suggests that calorie burn from exercise may be partially offset by metabolic adaptation, especially at very high levels of activity. However, research consistently shows that increasing physical activity raises total energy expenditure and supports fat loss, even if the increase is not perfectly linear.
2. Is the Additive Model of calorie burning outdated?
No. The additive energy expenditure model remains the foundation of metabolic ward studies, athlete fueling strategies, and clinical weight-loss interventions. While metabolic adaptation can reduce the size of calorie deficits over time, energy balance remains the governing principle behind weight change.
3. At what activity level does metabolic compensation occur?
Compensation appears most pronounced at extremely high activity volumes, such as ultra-endurance training lasting many weeks. For most people, moving from sedentary to moderately active levels (e.g., walking daily or strength training) still increases total energy expenditure meaningfully.
4. Does resistance training follow the same constrained pattern as endurance exercise?
Current evidence suggests that resistance training may not produce the same degree of metabolic compensation as prolonged endurance events. In fact, resistance training can increase lean mass and resting metabolic rate, supporting long-term improvements in energy expenditure and body composition.
5. Should people stop exercising if weight loss is slower than expected?
Absolutely not. Exercise improves metabolic health, preserves muscle mass during dieting, enhances insulin sensitivity, and supports long-term weight maintenance. Even if calorie burn is partially compensated, physical activity remains one of the most powerful tools for overall health and sustainable fat loss.
References
Clark J. E. (2015). Diet, exercise or diet with exercise: comparing the effectiveness of treatment options for weight-loss and changes in fitness for adults (18-65 years old) who are overfat, or obese; systematic review and meta-analysis. Journal of diabetes and metabolic disorders, 14, 31. https://doi.org/10.1186/s40200-015-0154-1
Gonzalez, J. T., Batterham, A. M., Atkinson, G., & Thompson, D. (2023). Perspective: Is the Response of Human Energy Expenditure to Increased Physical Activity Additive or Constrained?. Advances in nutrition (Bethesda, Md.), 14(3), 406–419. https://doi.org/10.1016/j.advnut.2023.02.003
Jakicic, J. M., Marcus, B. H., Gallagher, K. I., Napolitano, M., & Lang, W. (2003). Effect of exercise duration and intensity on weight loss in overweight, sedentary women: a randomized trial. JAMA, 290(10), 1323–1330. https://doi.org/10.1001/jama.290.10.1323
Le Page, M. (2026, February). Why exercise isn’t much help if you are trying to lose weight. New Scientist. Retrieved February 11, 2026, from https://www.newscientist.com/article/2514600-why-exercise-isnt-much-help-if-you-are-trying-to-lose-weight/
MacKenzie-Shalders, K., Kelly, J. T., So, D., Coffey, V. G., & Byrne, N. M. (2020). The effect of exercise interventions on resting metabolic rate: A systematic review and meta-analysis. Journal of Sports Sciences, 38(14), 1635–1649. https://doi.org/10.1080/02640414.2020.1754716
Most exercise burns fewer calories than you think — new study. (2026, February 11). New York Post. Retrieved from https://nypost.com/2026/02/11/health/most-exercise-burns-fewer-calories-than-you-think-new-study/
Pontzer, H., & Trexler, E. T. (2026). The evidence for constrained total energy expenditure in humans and other animals. Current Biology. Advance online publication. https://doi.org/10.1016/j.cub.2026.01.025
Thurber, C., Dugas, L. R., Ocobock, C., Carlson, B., Speakman, J. R., & Pontzer, H. (2019). Extreme events reveal an alimentary limit on sustained maximal human energy expenditure. Science advances, 5(6), eaaw0341. https://doi.org/10.1126/sciadv.aaw0341
Woods, R. (2025, October 28). The exercise paradox: Why workouts aren’t great for weight loss but useful for maintaining a healthy body weight. The Conversation. Retrieved from https://theconversation.com/the-exercise-paradox-why-workouts-arent-great-for-weight-loss-but-useful-for-maintaining-a-healthy-body-weight-266715
Wu, T., Gao, X., Chen, M., & van Dam, R. M. (2009). Long-term effectiveness of diet-plus-exercise interventions vs. diet-only interventions for weight loss: a meta-analysis. Obesity reviews: an official journal of the International Association for the Study of Obesity, 10(3), 313–323. https://doi.org/10.1111/j.1467-789X.2008.00547.x
