What is the effect of endurance training on resting heart rate?

Endurance training typically leads to a decrease in resting heart rate. This phenomenon occurs as a result of several physiological adaptations that develop with consistent aerobic exercise.

During endurance training, the heart becomes more efficient at pumping blood. The stroke volume—the amount of blood the heart pumps with each beat—increases due to improved cardiac muscle strength and volume. As a result, the heart can deliver the same amount of blood to the body with fewer beats. This enhanced efficiency allows the resting heart rate to decrease, as the heart does not need to work as hard to supply oxygen and nutrients to the body at rest.

Additionally, endurance training fosters adaptations in the autonomic nervous system, particularly an increase in parasympathetic tone (the part of the nervous system responsible for rest and digestion), which also contributes to a lower resting heart rate. Overall, these adaptations signify improved cardiovascular fitness and a more efficient circulatory system, characteristic of individuals who engage in regular endurance training.