Regular physical activity is essential for maintaining cardiovascular health, with aerobic exercises being particularly effective. According to the American Heart Association, 150 minutes of moderate to intense aerobic exercise per week is recommended for a healthy heart. Aerobic activities may include brisk walking, running, bicycling, cross-country skiing, and swimming, ideally performed three to five times per week.
Sustained exercise increases the muscles' oxygen demand, which can be met through adequate cardiac output and proper respiratory system function. With consistent training over several weeks, a person can increase their maximal cardiac output, the volume of blood ejected from the heart's ventricles into the arteries each minute. This improvement enhances oxygen delivery to the tissues. Additionally, long-term training promotes the development of more capillary networks in skeletal muscles, further improving oxygen delivery.
The heart of a well-trained athlete can double the cardiac output compared to a sedentary person due to physiological cardiomegaly, an enlargement of the heart caused by training. Despite this increased size, the resting cardiac output of an athlete is similar to that of a healthy, untrained person, as the stroke volume (the volume of blood pumped with each heartbeat) increases while the heart rate decreases. Athletes often have a resting heart rate of only 40-60 beats per minute (resting bradycardia).
Regular exercise has additional health benefits beyond cardiovascular improvements. It can help reduce blood pressure, anxiety, and depression, control weight, and prevent the formation of blood clots, contributing to overall well-being.