“The practice of Yoga is linked to the Nāḍī, or pulse, so he always thinks that the pulse rate tells whether you have done a good practice or a bad practice.

He suggests that our life may be measured by the number of beats to the heart, and if somebody wants to live long and well, he has to reduce the rate of the heart beat.

This is, of course, a little different from what the aerobic people say, who think you should boost your heart rate to 130/140.”

– TKV Desikachar from lectures on ‘The Yoga of T Krishnamacharya’,
given at Zinal, Switzerland 1981.