Sure. I think that's still done -- I mean, look at top-tier racers.

But fasting and cutting weight are different ideas.

I just meant that cutting calories while cycle training has a long history (though I would describe it as healthy)

Diet modification during training typically still involves eating more calories than a sedentary person.

I know less about cycling diets than I do fighter camps but it is incredibly common for fighters to eat at fasting levels while continuing to train. The strict weight requirements cause that.

I was of the impression that it used to be the case that cyclists did this but that it was out of fashion now.

In any case lots of people do 1500 calorie efforts at fasting intake levels. It’s not healthy long term but it’s completely ‘normal’ for done athletes.