hi William, as the heart becomes able to pump a higher amount of blood (increased stroke volume), your heart rate will reduce both at rest and during exercise. The reduction of heart rate at rest typically can come also with a slightly increased HRV (there's more time between beats, hence this can add some variability). While changes in resting heart rate with training are widely reported, changes in HRV are maybe a bit less consistent or less marked, but a slight increase is often seen, at least for people taking up exercise. There might also be an increase in parasympathetic activity with exercise, that is not only associated to the change in heart size, that might also impact HRV positively.
How does adaptive modifications in heart (increased size L ventricle and murmur) affect HRV?
hi William, as the heart becomes able to pump a higher amount of blood (increased stroke volume), your heart rate will reduce both at rest and during exercise. The reduction of heart rate at rest typically can come also with a slightly increased HRV (there's more time between beats, hence this can add some variability). While changes in resting heart rate with training are widely reported, changes in HRV are maybe a bit less consistent or less marked, but a slight increase is often seen, at least for people taking up exercise. There might also be an increase in parasympathetic activity with exercise, that is not only associated to the change in heart size, that might also impact HRV positively.