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The cardiac cycle involves rhythmic contractions of the heart:
During diastole, the heart muscles relax, allowing chambers to fill with blood.
During systole, the ventricles contract, ejecting blood into arteries.
Advanced imaging like MRI captures these motions vividly, showing the ventricles contracting and relaxing, propelling blood through valves and vessels in a continuous, efficient loop.
Heart Rate and Its Regulation
The heart rate measures how many times the heart beats per minute (BPM). Typically, a resting adult's heart rate ranges from 60 to 100 BPM, but factors like physical activity, stress, age, health, and environmental conditions can influence this rate.