As VO2max increases, what happens to heart rate during sub-maximal exercise intensity?

When considering the relationship between VO2max and heart rate during sub-maximal exercise intensity, it is important to understand how cardiovascular function adapts to fitness levels. VO2max represents the maximal volume of oxygen that an individual can utilize during intense exercise and is a strong indicator of aerobic fitness.

As an individual's VO2max increases, their cardiovascular system becomes more efficient. This efficiency means that the heart can pump more blood with each beat due to improved stroke volume, which is the amount of blood pumped from the heart per beat. Consequently, when an individual with a higher VO2max engages in sub-maximal exercise (which is exercise performed below maximal effort), the heart does not need to work as hard to deliver the requisite oxygen to the muscles compared to someone with a lower VO2max.

Thus, for someone with a higher VO2max, the heart rate during sub-maximal exercise tends to decrease. This is because the body is able to meet the demands of the exercise with fewer heartbeats, reflecting increased efficiency. As a result, sub-maximal exercise appears less demanding on the cardiovascular system, resulting in a lower heart rate for a similar intensity of exercise. This adaptation showcases improvements in cardiovascular fitness and efficiency as represented by a higher VO2max