Is Exercise Actually Good For Weight Loss?

How effective is exercise for weight loss? In the past, going to the gym or running was synonymous with losing weight. However, recently, that idea has been challenged. Some argue that exercise doesn't really help with fat loss as it only burns a few calories.

Others argue that when you exercise, your metabolism adapts so you don't actually burn as much as you think you did; this is called the constrained energy expenditure model.

How Does Exercise Help Burn Fat?

Over the past few years, there has been an increase in posts and content suggesting exercise actually isn't great for fat loss. Some of the reasons include;

• Exercise doesn't burn that many calories.
• Training makes you hungry, so you eat more, which offsets the calories you burn.
• Your body adapts to increased activity to burn calories.

This message can be harmful, leading people to abandon exercise even though it is extremely important for long-term weight loss.

Therefore, let's examine the role of exercise in calorie burning and weight loss.

Exercise Increases Your TDEE

Total Daily Energy Expenditure (TDEE) is the total number of calories you burn in a day. This is 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

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.

Of these, Activity is the most controllable part of TDEE. Unlike basal metabolism and TEF, you can intentionally increase activity to influence daily calorie burn. 

Resistance Training Maintains And Builds Muscle Mass

We always tell our clients that when losing weight, the gym's primary benefit is not calories; it's maintaining or building muscle.

During calorie restriction, the body is more prone to losing muscle. This is especially true when it's not paired with resistance training. If so, you're at risk of;

• Decreasing BMR and total calories expended
• Losing strength
• Decreasing aesthetics 

This is not what you want. Therefore, we tell our clients that their main goal for going to the gym is to mitigate muscle loss. Training will help you. 

• Maintain lean mass
• Prevent metabolic slowdown 
• Optimize body composition

This is why all of our fat loss programs include strength training!!

Can Exercise Help Improve Hormones?

Exercise and hitting the weights can completely alter your hormones in a good way. Many of these have a much greater impact on long-term weight loss than the calories you burn.

Here's a quick list of hormones that are improved and how they help with weight loss.

• Leptin – Signals satiety and energy sufficiency, supporting appetite regulation.
• Ghrelin – The "hunger hormone"; regular resistance training may blunt excessive increases in ghrelin that often occur with calorie restriction
• Insulin – Improves insulin sensitivity, directing nutrients toward muscle instead of fat storage.
• Epinephrine & Norepinephrine – Stimulate lipolysis (fat breakdown) during and after training
• Growth Hormone (GH) – Supports fat mobilization and recovery.
• Testosterone – Helps maintain lean mass, protecting metabolic rate during fat loss

Low muscle mass is now recognized as an independent risk factor for diabetes, regardless of fat mass (Son et al., 2017). If your body has nowhere to store glucose, it stays in your bloodstream, resulting in high blood sugar.

Improves Executive Function and Cognition.

Regular exercise makes you feel good by increasing dopamine and serotonin activity. This leads to reduced stress-driven eating and emotional decision-making.

One of the lesser-known benefits is that it strengthens cognition and executive function (Singh et al., 2025; Huang et al., 2022). This is critical during fat loss as it controls the brain's ability to;

• Plan ahead
• Delay gratification
• Regulate impulses
• Stay goal-oriented

This is one of the reasons why you often hear people say things like "it gets easier as you go".

In this way, exercise supports weight loss indirectly by improving the mental architecture required for sustained behavioral change. It really does make losing weight easier.

Can You Lose Fat With Exercise And Training?

Absolutely. People strongly undervalue the role that exercise and training have in fat loss. 

Many chalk it up to just burning some calories and believe it doesn't make that much difference. This is 100% wrong.

The vast majority of studies clearly show that, compared to diet alone, weight-loss protocols that combine diet and exercise produce greater results (Clark et al., 2015; Wu et al., 2009). Some of the weight loss benefits of exercise include: 

• Increasing calorie burn
• Increasing your RMR (metabolism)
• Improving glucose metabolism
• Improving hormones
• Increasing executive function (can help with dieting)
• Mitigating muscle loss (weight training)

While exercise and training directly benefit and optimize weight loss, there's perhaps a more important benefit.

Long-Term Adherence.

For weight loss to be effective, it must be sustained, and this is one of the downfalls of diet alone.

Research has shown that adding exercise not only improves the results but also increases your chance of maintaining a healthy weight (Wu et al., 2009).

Can You Lose Fat With Exercise Alone?

While we don't recommend this, exercise alone can result in weight loss.

When comparing diet alone and exercise alone, research has found that exercise can lead to greater weight loss and better body composition.

"Most importantly, protocols utilizing exercise were more effective than those that employed just a hypocaloric diet" (Clark, 2015).

Now, obviously, these individuals still got better results when paired with intentional dieting, but this is a strong testament to the power of exercise. 

Does Your Metabolism Adapt To Exercise?

It can, but not to the extent some influencers suggest. 

The idea is called the Constrained Total Energy Expenditure Model, which suggests your metabolism can adapt to increased activity levels.

For example, increasing your activity by 500 calories might result in only a 300-calorie decrease, as your BMR can fluctuate throughout the day and during sleep.

While more research is needed, it appears this does occur, primarily affecting very high activity levels. A good illustration for this is when researchers tracked a 5-month-long endurance race (Thurber et al., 2019).

• Runners ran the equivalent of 6 marathons per week for 14-20 weeks.
• The first week, they burned 6,200 calories.
• By week 20, their expenditure was 20% below expectations.

It's important to note that even though these were endurance athletes, their energy expenditure met expectations during the first week. This suggests the drop was due to prolonged, daily, extreme exercise rather than permanent alterations.

In addition, this is the largest applied metabolic study to date with extreme levels of activity, i.e., as bad as it gets.

The authors of a review stated;

This is a much more nuanced topic to discuss in totality, so we have a dedicated article for it here. 

Can Exercise Help Lose Weight? Final Say

We're not sure where this messaging came from, but you can definitely lose weight with exercise. In fact, exercise has always been a central component of any weight loss program.

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.

It's a powerful tool, which is why we always promote exercise, specifically a program that includes resistance training and cardio, like our SFS Fat Loss Program.

Or, if you think you need further assistance, send us an email, and we can get you started right!

FAQ: Is Exercise Actually Good For Weight Loss?

Does exercise really help with weight loss, or is it mostly diet?

Both matter. Diet determines whether you're in a calorie deficit, but exercise increases total daily energy expenditure and improves body composition. Research consistently shows that combining diet + exercise produces greater fat loss and better long-term results than diet alone.

Does your metabolism "adapt" and cancel out the calories you burn?

Metabolic compensation can occur, but it does not fully cancel out exercise. The constrained energy model suggests diminishing returns at very high activity levels, not that exercise is useless. For most people, increasing activity still results in a meaningful net increase in calories burned.

Is resistance training better than cardio for fat loss?

Resistance training plays a unique role because it preserves or builds muscle mass during weight loss. Maintaining muscle protects resting metabolic rate and improves body composition. Cardio can increase calorie burn, but strength training is critical for preventing metabolic slowdown.

Can you lose weight with exercise alone?

Yes, but it's less efficient than combining exercise with intentional calorie control. Exercise alone can reduce body fat and improve composition, and some research suggests it may outperform diet-only approaches in preserving lean mass. However, pairing training with dietary control yields the best results.

Why is exercise important for long-term weight loss?

Exercise improves executive function, mood, insulin sensitivity, and muscle mass — all of which support adherence. Weight loss isn't just about burning calories; it's about sustaining behaviors. Exercise increases the likelihood that fat loss efforts are maintained rather than regained.

References

1. 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
2. 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
3. Huang, T. Y., Chen, F. T., Li, R. H., Hillman, C. H., Cline, T. L., Chu, C. H., Hung, T. M., & Chang, Y. K. (2022). Effects of Acute Resistance Exercise on Executive Function: A Systematic Review of the Moderating Role of Intensity and Executive Function Domain. Sports medicine - open, 8(1), 141. https://doi.org/10.1186/s40798-022-00527-7
4. 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 
5. 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/
6. 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 
7. 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
8. Son, J. W., Lee, S. S., Kim, S. R., Yoo, S. J., Cha, B. Y., Son, H. Y., & Cho, N. H. (2017). Low muscle mass and risk of type 2 diabetes in middle-aged and older adults: findings from the KoGES. Diabetologia, 60(5), 865–872. https://doi.org/10.1007/s00125-016-4196-9
9. Singh, B., Bennett, H., Miatke, A., Dumuid, D., Curtis, R., Ferguson, T., Brinsley, J., Szeto, K., Petersen, J. M., Gough, C., Eglitis, E., Simpson, C. E., Ekegren, C. L., Smith, A. E., Erickson, K. I., & Maher, C. (2025). Effectiveness of exercise for improving cognition, memory and executive function: a systematic umbrella review and meta-meta-analysis. British journal of sports medicine, 59(12), 866–876. https://doi.org/10.1136/bjsports-2024-108589
10. 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
11. 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