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Catabolism = The breakdown of body tissue for whatever reason.... primarily energy.
Anabolism= The building of body tissue.
You are always catabolic when using body fat for energy. You are being anabolic when building muscle or storing fat. If you are fat adapted yet eating a ton.... i.e. more than what you are breaking down for energy, then by definition you are being more anabolic as you are storing more. If you are breaking down more fat than you are taking in then by definition you are in a more catabolic state. What state you are in at this very moment depends mostly on the last time you ate and sleep/wake.
Catabolism is so often mentioned primarily in the context of muscle burning/lean body mass loss rather than fat burning, I'm guessing that might be what you meant?
It is still possible to lose lean body mass while fat adapted, or even ketogenic. There are limits to how much fat you can burn and how much of a deficit you can sustain before losing lean tissue. The numbers aren't certain as far as I know, but one study suggested that the daily caloric limit for stored fat burn is 31 calories multiplied by however many pounds of fat you have on your body. So, someone who weighs say 180 at 15% body fat will have 27lbs of fat, putting their daily limit for calories burned from stored body fat at 837 (27 x 31). If they were to exceed that, they risk losing lean mass. Someone at 300lbs and 33.3% body fat will have 100lbs and 3100 calories. It's part of why it gets so difficult to reach single digit body fat percentages. I don't think this was completely proven, and individual bodies will of course vary anyway, but it doesn't seem far off, plus it's the only number out there for this, at least that I know of.
However, it also seems that in very deep fat burning/ketosis, it's actually possible to burn fat while not only maintaining, but building lean mass. Long thought to be metabolically impossible, but apparently not. A doctor named Jeff Volek recently did an experiment and got exactly this result, there's some good info on youtube about it if you search around.