So we have phosphorinopyruvate that is transformed into pyruvate molecules and ATP molecules by the activity of pyruvate kinase. Now just like phosphor, fructokinase is inhibited by ATP molecules. So it's pyruvate kinase. So when there's a rise in ATP, when we have a high energy charge value in the cell, when we're not exercising, we have too many ATPs. And so the ATP acts as a signal to basically inhibit the activity of pyruvate kindness. It creates a negative feedback loop, an inhibition loop.