When the blood volume is sufficient, the heart contracts, ejects blood, and the arterial blood pressure rises. The highest value of blood pressure rise is called systolic blood pressure. Diastolic pressure is the lowest value of diastolic pressure. Normal people's blood pressure gradually increases with age and fluctuates under different physiological conditions. For example, people's blood pressure drops during sleep, but rises during exercise. Generally speaking, normal people's resting systolic blood pressure is less than18.7kpa (140mmhg) and diastolic blood pressure is less than12.0kpa (90mmhg). If the systolic blood pressure is > 2 1.3 kPa (160mmhg) and/or
Low pressure is not higher than 90, and high pressure is not higher than 140.