If you exersize a lot, your body will ask for a lot more food. Your body does not want to starve, and using a bunch of calories without replacement leads to that result.

At some point you have to control your diet. But, if you can control your diet, the exersize clearly isn't a requirement.

I find that’s only true for the first few months of training while you get the beginner gains. Running half an hour a day was by far the biggest contribution to my weightloss once I finished the couch to 5K program and my diet settled down. My body adapted relatively quickly to the new regime just like it did with my sedentary lifestyle but YMMV.

Once you can run frequently without gorging afterwards, the extra 300-500 calorie buffer makes dieting a million times easier.

(Lost 35 pounds in 2024, 90% of it during weeks in which I ran consistently)

A lot of that is based on assumptions from the 50s and 60s, which have been proven false in the late 80s by more rigorous studies.

When you increase activity, over the course of weeks, the body adjusts and does everything it can to not touch those fat stores.

Case in point: women who exercise intensely experience a reduction in the production of sex hormones, as that is energy intensive.

That's really interesting – though it appears it's a general human thing. https://pmc.ncbi.nlm.nih.gov/articles/PMC7739287/

> TT and FT began to decrease starting 12 weeks in both moderate and high intensity exercise groups. Most significant decrease was at 12 weeks in high intensity exercise group

> When you increase activity, over the course of weeks, the body adjusts and does everything it can to not touch those fat stores.

Your body doesn't adjust endlessly. The technique to continue to shift body composition is called progressive overload, this isn't outdated and is the basis of most athletic training regimens.

Again I want to reiterate that no one is suggesting that diet isn't the foundation of fitness and controlling body composition. I am simply and factually stating that you can use exercise as a lever to achieve a calorie deficit. Arguing otherwise is to argue against thermodynamics, moving your body consumes energy and you body simple cannot achieve perfect efficiency.