It get worse. Apparently, your body adjust its basal metabolism over the long term in response to daily physical activity.
Re:Adult Obesity Facts
by osigurdson on Friday August 27, 2021 @02:01PM
(#28331038)
While I am not completely convinced that it works to greatly improve fitness, I can attest that the low heart rate running approach (google Maffetone:180 - age) approach does not seem to increase appetite at all.
Running a 5k doesn't even burn 500 calories for most people, but you can eat that much in snacks without a second thought. To really make a difference in weight the much more important side of the equation is intake.