alt Hacker NewsMeh..not as much as you hope or expect. There is a popular channel on youtube @ErikTheElectric who does these huge food challenges, but also tons of cardio like marathons and 100-mile bike rides, to try to offset it. He weighs 170. At his height I weigh 15 lbs less, simply from eating less despite doing much less cardio than him. The body is very good at increasing its efficiency in response to exercise. You will be working your ass off doing cardio, but the weight just not budging much beyond water fluctuations. Many people report this. They will do 20-thousand steps and stop losing weight after a few days.
As for muscle, a pound only burns 11 calories/day. You'd have to gain 20 lbs of muscle, basically become a bodybuilder, just to offset a KitKat. The math is pretty depressing.
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That's a common misunderstanding but efficiency doesn't actually change much based on exercise. You can verify this with metabolic tests that measure inhaled and exhaled gases.
In my experience, full body sports (krav maga in my case) are the exception here. It's super easy to stay lean if you eat normally and do this kind of thing. My explanation for this is that the body adapts very well to using a single set of muscles because it expects to have to do it for a long time, like when hunting or gathering, but full body means you are fighting for your life. I think this is also why lifting heavy works so well too. (I have no credentials or training in this area, just my own xp, so treat this as wild speculation of course.)