You’re not burning as many calories working out as you think you are

• Our bodies compensate for the calories burned during workouts by expending fewer calories throughout the remainder of the day.
• For every 100 calories you expect to burn while exercising, you actually burn fewer than 72 calories.
• In order to optimize exercise for weight control, you need to learn how your metabolism reacts to exercise.

Exercise isn’t burning as many calories as you had hoped. Sound familiar? 

Despite thinking that working out harder and longer is the way to shedding more calories, a new study finds that for every 100 calories that one expects to burn while exercising, most will only burn fewer than 72 calories, meaning weight loss through exercise just got a lot harder.

How our bodies adapt to exercise

The study, published online in Current Biology, finds that our bodies compensate for the calories burned during workouts by expending fewer calories throughout the remainder of the day.

It’s bad news for people who thought that spending extra time in the gym would lead to increased weight loss. But all hope isn’t lost — the study says that calorie compensation varies from person to person, which means in order to optimize exercise for weight control, you need to learn how your metabolism reacts to exercise.

The study focused on data from 1,750 adults finding that in individuals with the highest body mass index (BMI), only 51% of the calories burned during a workout translated into calories burned at the end of the day. For individuals with normal BMI, 72% of calories burning during exercise are reflected in the number at the end of the day.

“When enrolled into exercise programs for weight loss, most people lose a little weight. Some individuals lose lots, but a few unlucky individuals actually gain weight,” John Speakman, professor at Shenzhen Institute of Advanced Technology, said in a statement.

The underlying reasons for differed responses in individuals are likely due to compensatory mechanisms, according to the study. This can include people eating more food because exercise stimulates our appetite or our body reducing its expenditure on other things like resting metabolism, making the exercise less costly.

Researchers said that that age-older people compensate more and people living with obesity decrease their resting metabolism when they are more active, resulting in fewer calories burned while resting.

“Around the world, national guidelines tend to recommend a 500–600 calorie deficit through exercising and dieting to lose weight. However, they do not take into account the reduction of calories being burned in the most basic of human functions as the body compensates for the calories burned on the exercise,” said University of Roehampton professor Lewis Halsey, lead author of the study.

More on exercise:

• If you walk at this time every day, you could add years to your life
• Doing this specific exercise will keep you young
• 6 ways to keep up with your fitness routines this fall