I wasn’t trying to be pedantic as such. It’s just that I found fitness when I was on a path to trying to bring my body fat down to a level I was happier with. I had originally though “losing weight” was healthy, but then I read that being active is more beneficial than losing weight, so I thought I needed to include a bit of fitness training in there.

And then when I started running, to my great surprise, I found out that I loved it, and I kept running. I ended up SUPER SUPER in to running. And one of the things that I discovered was that after a period of trying to watch how much I eat, when my training peaked, I was often struggling to get enough calories to match my burn.

And I often joked to myself back then that if I’d have known I could have outrun my bad diet, I’d have started there :P

But in all seriousness, as you said, it’s not possible to sustain. Age, injury, decreased training levels, eventually, something happens and your calorie burn returns to more regular levels, and then you’re not outrunning it anymore