Cardiovascular exercise involves the use of large muscles in a repetitive fashion, activating muscle fibers programmed for endurance and utilizing a heart rate range anywhere from 40 to 85 percent of your maximum heart rate. Think: running, jogging, swimming, biking, or spinning.
How does cardiovascular exercise affect your heart?
When performing cardio, blood flow is directed toward working muscles and away from areas that aren’t doing much (such as your arms during running, or the digestive tract). There is increased blood flow, and blood volume returning to the heart.
As the heart registers a larger blood volume, over time the left ventricle adapts and enlarges. This larger cavity can hold more blood, and ejects more blood per beat, even at rest.
More: Calculate your Target Heart Rate.
Over time, with chronic cardio training, our resting heart rate drops because each beat delivers a bigger burst of blood, and fewer beats are needed. This takes work off your heart and is why cardio exercise is recommended for heart health.
However, cardiovascular exercise can also produce stress. If we get into over-training, we may hit a point where we are drowning in cortisol. This eventually leads to immune-suppression and fat gain around the abdomen and face.
People who spend a significant part of their day in stress, who have poor digestion or other sources of physiological stress, should not further their stress levels by overtraining. Always think of your goals, moderate your exercise if necessary, and work to reduce your stress levels
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