well from what I know from what's written on the subject... and what I've experienced, If your body is in a ketogenic state, and you are eating foods with fat in em, it will utilize the incoming fats before using up your fat deposits.. so in reality morning cardio in the "fasted" state would still be more effective. The morning cardio thing isn't just about glucose, it's more complicated than that. If you have tried doing keto diets and trying both ways (morning cardio without food, or cardio later in the day) you can still feel the difference in your body.. that's my opinion.