How much energy is stored as Glycogen in our muscles?

Question

I want to know when Glycogen stores are depleted and when the body starts breaking down its fat reserve. I need the energy expressed in terms of Kcalories

Answer 1

"Glycogen debt and distance racing
Due to the body's ability to hold no more than around 2,000 kcal of glycogen, long-distance athletes such as marathon runners, cross-country skiers, and bicycle racers go into glycogen debt, where almost all of the athlete's glycogen stores are depleted after long periods of exertion without enough energy consumption. This phenomenon is referred to as "hitting the wall" or "bonking". In marathon runners it normally happens around the 20 mile (32 km) point of a marathon, where around 100 kcal are spent per mile, depending on the size of the runner and the race course. When experiencing glycogen debt, athletes often experience extreme fatigue to the point it is difficult to move"