"Systolic" refers to the phase of the heartbeat when the heart muscle contracts and pumps blood out of the chambers. This phase is crucial for circulating oxygen-rich blood throughout the body. The systolic pressure is the higher number in a blood pressure reading, indicating the force of blood against the artery walls during this contraction. In a typical blood pressure measurement, such as 120/80 mmHg, the "120" represents the systolic pressure. Monitoring systolic pressure is important for assessing cardiovascular health, as elevated levels can indicate conditions like hypertension or increase the risk of heart disease.