The contraction is known as systol or systolic. And the relaxation is diastolic or diastolic. So when it contracts, and then when the left ventricle is filling to get ready for the next beat because it has to fill back up with that. That is what we call diastole. Right at the very end of diastole, you have a particular volume of blood, which unsurprisingly, we can call the end diastolic volume. On average, it's about 70 milliliters per beat. But there's things that can affect the filling and the emptying. And again, these are factors that affect stroke volume, but also factors that