When the body is fueled predominantly by glucose, it builds up stored glucose as glycogen, which is then broken down for energy.

“if you are fueled predominantly by let's start with GL glucose so predominantly by carbohydrates then the fuel supply you're building up is the form of stored glucose which is glycogen right so you're building it up and then when you're done eating you're breaking it down over time and you're being fueled by it in large part if that's a predominant part of your diet”