What is so difficult to understand about this TRUTH, that I could eat 3,000 calories a day from starchy carb-heavy sweets and I would definitely get fat, fat, fat on doing EXACTLY THE SAME AMOUNT OF EXERCISE as I can do consuming 3,000 calories a day -- "the same calorie content" -- from mostly animal protein and fat, non-starch vegetables, fruits, dairy, and low carbs.
How do I know?
Because I have lived it. :^) I understand it very well.
You may be doing a similar exercise routine but if you measure the quantity of calories burned, and it is still 3000, then where do the extra calories come in for the fat deposition. Fat is a very calorie dense tissue. Perhaps you simply slowed your metabolism and didn’t burn the 3000 calories you thought you were burning. No question that different foodstuffs are metabolized by different pathways.