It opens up the activity and that causes, it increases the activity of this phosphorase B. And so what that will do is it will stimulate the phosphorlase B to actually go on and break down the glycogen into glucose molecules to form more ATP. Now in addition, sudden or strenuous activities such as for instance sprinting will basically stimulate the release of specific hormones, for instance epinephrine. And what these hormones basically do is they stimulate the enzyme phosphorase kinase. And remember, phosphorase kinase uses ATP to transform the phosphoralase B which exists predominantly in the inactive T state, into phosphorlase A which exists predominantly in the r state. And what that does is it helps us produce more ATP molecules by breaking down glycogen into glucose and using the glucose in glycolysis to form those ATP.