Some people stop losing weight even when they keep exercising and eating the same amount, because their bodies may lower energy use in other functions to balance out the extra activity.

When people exercise regularly over a long time, their bodies may lower energy use in other functions, such as metabolism or cellular processes, which can reduce the amount of weight lost compared to what would be expected based on calories burned through exercise alone.

After losing weight through dieting, keeping the weight off typically requires higher levels of physical activity because the body naturally reduces energy use and increases hunger, making it difficult to maintain weight loss by eating less alone.

After losing weight, obese adults who increase their physical activity and calorie intake to match energy expenditure show a slightly higher resting metabolic rate and reduced feelings of hunger compared to those who remain sedentary and eat less.

After losing weight, obese adults who maintain higher levels of physical activity and food intake have a slightly higher resting metabolic rate than those with lower activity and intake, resulting in an increase of about 79 calories burned per day at rest.

When people burn calories through cardiovascular exercise, their bodies often respond by increasing food intake or reducing daily movement, which can limit the amount of fat lost overall.