it seems that many people just blindly refer to the 20 minute mark in cardio, which is just the amount of time that everyone assumes it takes to burn all of the muscles stored glycogen, right?
So what if you ideally have very little glycogen stored in your muscles due to a low carbohydrate lifestyle and your body mostly relies on burning ketones as a primary energy source. Does this 20 minute mark still apply?
Am I completely off base?
(also assuming that your protein intake is at a level that help will minimize muscle loss)