So what is the ultimate fate of lactate? Well, once lactate moves across the membrane of these erythrocytes and skeletal muscle cells and enters the bloodstream of our cardiovascular system, the blood plasma, it generally ends up in one of two locations cardiac muscle cells and liver cells. And so let's focus on the following diagram as we go along this text. And let's imagine that we're essentially sprinting. So as we begin to sprint initially what happens in our skeleton muscle cells? So in that skeleton muscle cell, we need to basically produce the ATP for the active mice and fibers to actually contract.