Does Exercise actually help you lose weight?

“Ok, I’m confused, EXERCISE isn’t good for me?”

No! Exercise is one of the leading ways to improve your health, decrease mortality, prevent cardiovascular disease, and prevent age-related physical and cognitive decline. Everyone should exercise 3-5 times a week for even just 30 minutes to improve their overall health.
BUT … Exercise shouldn’t be used as a mechanism for long-term weight loss.
I love hearing personal trainers preach about Calories-In vs Calories-Out when not many understand what “Calories-Out” means. It isn’t as straight forward as we once thought.
There are Three major ways our body uses calories: Basal Metabolic Rate, any Physical Activity, and the Thermogenic effect and mechanical digestion of the food we consume.
The common mantra is, that if we increase 1 of the 3 from above, we will increase our total calories burned! I.e. if i just exercise MORE I will increase my “calories-out”.
Well not exactly. First, physical activity only accounts for about 10-15% of the total calories burned in a given day. This includes all activity: brushing your teeth, commuting to work, getting off the couch, going to the gym. So exercise may only account for a small piece of the total pie. But what most people don’t realize is that if you increase that portion, two things are working against you. One: when you exercise in the morning, parts of your body may adapt later on to burn fewer calories as a form of metabolic compensation. This has been studied quiet extensively and studies show that for those individuals who exercise repeatedly, their bodies actually become more efficient and while their Physical Activity calories increase, their basal metabolic rate decreases. Two: Our behavior changes when we exercise. Most of us over guesstimate how many calories burn when working out, or we under guess how many calories are in our foods. So after we workout, we are more likely to eat more or eat foods that may be more caloric dense negating the calorie burning effects of exercise.
As always, I know this is a hot topic! I personally workout every single day and one caveat to note is that this doesn’t always hold true for everyone nor does it hold true for elite athletes! Often times exercise helps us lose weight initially, but after a couple of months, we either reach a plateau or we gain it all back after we stop working out.
I struggled originally writing this post because exercise still is one of the best ways to improve your health and is the best way to start any healthy lifestyle changes, but it should not be looked at as a tool to lose weight. I didn’t want to give the impression I am against exercise! FALSE! I am 100% FOR exercise! But you can’t workout of a bad diet from an overall health perspective.
Everyone should still exercise! The effect on body composition, personal well-being, insulin resistance, & disease prevention is huge; especially for diabetes, age related degeneration and cardiovascular disease! To actually lose weight from exercise you need to change your diet and what calories you put in! For some, working out helps them make healthier food choices, but that is not the case with everyone. The best chance to improve health and lose weight is to look at it holistically not relying on any one factor. Exercise, Nutrition, Sleep, Hydration, etc.
As always I love answering your questions! Attached are a few of the articles I used to make this post. You can find links to everything on the post on my blog today!

Effect of Exercise Intensity on Spontaneous Physical Activity Energy Expenditure in Overweight Boys: A Crossover Study

Resistance to exercise-induced weight loss: compensatory behavioral adaptations

Is there spontaneous energy expenditure compensation in response to intensive exercise in obese youth?

Why do individuals not lose more weight from an exercise intervention at a defined dose? An energy balance analysis

Changes in Weight, Waist Circumference and Compensatory Responses with Different Doses of Exercise among Sedentary, Overweight Postmenopausal Women


Disclaimer: All opinions are my own. I do not provide medical advice. If you have questions please ask your doctor & do your own research. I am still a medical student and a PhD candidate. I have 5 degrees including 2 masters in nutrition & metabolism. I am a certified personal trainer & have researched these topics for 9 years. The information I post is research based & is information not always taught in school.

Hi! I am a third-year medical student and third-year PhD candidate with a passion for innovation, biomedical research, medical education, healthcare policy, biotechnology, nutrition and a healthy lifestyle. I am a bit of a non-traditional student as you can see from my personal bio. I am a host of medical podcast and the owner of an admission company focused on helping students get into the school of their dreams. I love educating and giving back so if you have questions feel free to email me!

What do you think?