Calorie counts concerning what people eat and what people burn during exercise are notoriously inaccurate. People tend to underestimate how many calories they eat and overestimate how many they burn. It’s why I always tell people to stop counting calories and instead focus on better food choices. I also typically recommend that you don’t subtract the calories you burn during exercise from your daily calorie totals. While it would make sense that if you burn 500 calories during a workout, then you should be allowed an extra 500 calories of food as a reward, but it never works out that way. Research has shown that this kind of thinking typically results in people eating twice as many calories as they burned. It’s one reason why so many people either don’t lose weight or actually gain weight when they first start exercising.
While exercise can help with weight loss, when it comes down to it, you have to change what you eat if you want to lose weight. New research from the journal Current Biology presents some interesting evidence to show that calorie-burning seems to plateau no matter how active you are. When people first start exercising to lose weight, they’ll often experience rapid success, but those fast drops will quickly slow down or even reverse as they get later into a program. I’ve already mentioned some of the subconscious tricks your body plays on you to prevent wait loss, such as subconsciously increasing the portions you eat or reducing the amount you move the rest of the day, but as the report in Current Biology shows, your daily calorie burn eventually drops as your fitness improves.
Your body adapts
As I’ve mentioned many times before, we were meant to live in a food-scarce environment, so it makes sense that your body would adapt to make sure you’re not just burning through energy that would be difficult to replace. That’s ultimately what fitness is. As you get more fit, you need less energy to move your body around. That’s great for daily living and to help you feel more energetic, but it hampers weight loss. So whether you’re running five miles a day, walking a few miles each day, or doing 10 minutes of high-intensity interval training (HIIT), your daily calorie burn will be roughly the same. It’s a bummer for people that want to quickly run the fat off, but it’s great news since any kind of activity will help, just get moving more. It explains the mystery of why HIIT seems to be as effective for weight loss (often more effective) as longer workout sessions, even though it burns a fraction of the calories.
When you look at those daily calorie calculators, they always ask if you’re sedentary or active, but maybe they shouldn’t. The researchers found that in large comparative studies very active people had similar daily energy expenditures as sedentary people. They were most surprised when they looked at a traditional hunter-gatherer tribe in Tanzania called the Hadza. They walked long distances each day and performed hard physical labor as part of their normal routine, and yet they had similar daily calorie expenditures as sedentary people in the US.
The bottom line is don’t assume the calorie number on that treadmill is accurate, and definitely don’t use it as an excuse to indulge in crappy food. Exercise will help with your weight loss routine by mobilizing and burning stored fat for fuel, but you need to eat right for it to work. Your body will always burn what’s coming in rather than tap into stored fuel, so you need to give it a reason to switch to stored fat.
If the only thing that matters concerning weight loss is diet, then why even exercise? Just like how a calorie is not a calorie with food, a calorie is not a calorie with movement. You may burn the same amount of calories sitting around compared to moving around (as you get more fit), but movement provides an amazing array of benefits. I used to workout 3 days a week, but as I’ve done more and more research on the benefits of exercise, I increased that to daily.
I already wrote one article explaining why everyone should strength train, but let me quickly summarize many benefits from exercise in general:
Increased longevity. I think right off the top, living longer is a pretty good reason. Your body comes with a cellular countdown clock called telomeres. They shorten as you age. Exercise keeps them longer which effectively rolls back your internal clock. Many studies have shown that shorter telomeres have been linked to many age-related condition like cardiovascular disease, cancer, diabetes, and Alzheimer’s disease.
Decreased risk of cardiovascular disease. Just 30 minutes of walking 5 days a week decreases your mortality risk by 50 percent. I wanted to emphasize this one separately because it’s the number one killer, and studies have shown that it doesn’t take a lot of effort to make a big difference in improving your health.
Reduce stress, anxiety, and depression. Exercise is a short-acting stressor, and it teaches your body to not react so strongly to other stresses in life. This blunted biological response to stress really helps reduce feelings of anxiety. Movement has also been shown to reduce depression. You don’t need to run a marathon to improve your mood, just get out and walk.
Boost your immune system. Increased blood flow rapidly delivers immune cells to all corners of your body, the increased temperature prevents invading organisms from replicating, and the reduced stress effect prevents cortisol from interfering with your immune system. It all works together to keep your body battling bugs year round.
Boost brain function and prevent dementia. Exercise increases the number of neurons in the brain, it keeps your brain functioning like it’s younger self as you age, and it wards off cognitive decline.
Improve blood sugar control. We eat a lot of sugar in this country and many others around the world, and too much sugar leads to significant health issues. Active muscle cells pull sugar out of your bloodstream without using insulin. This means your body uses less insulin to get the job done which prevents all kinds of problems down the road caused by insulin-intolerance like diabetes, heart disease, and many forms of cancer.
Eat right, move more, ignore the numbers
Don’t focus on the numbers, just focus on moving more and eating quality foods and the weight loss will come. Your calorie burn will slow down as you get more fit, which is fine. I’ve seen people go nuts trying to workout 3 hours a day when 30 minutes is plenty. Pushing yourself so hard will just lead to burn out and possible injury. Find the right balance that works for your life. Just like how you’ll only have success if you eat healthy foods you enjoy, you also need to find activities that you like so that you’ll stick with it long term. We were meant to move, and things fall apart when we stop. You should exercise because it will keep you young, help you feel physically and mentally better, and drastically improve your health, but don’t overdo it chasing some one-size-fits-all number on your calorie-counting spreadsheet.