Kapalabhati has a tremendous impact on improving the nervous response we have towards breathing.. In fact, kapalabhati has to be regularly practiced to improve your stamina in the other breathing practices... The rate has to be progressively increased to 120 hyperventilations in one minute. The speed in kapalabhati -- and your comfort in it -- is what determines your nervous response in breathing practices and your ability to withstand stress! Regular practice of intense kapalabhati (has to be phased, obviously, since it makes the heart beat fast, hikes the blood pressure and causes intense hyperventilation). This helps you be calmer when you do other pranayama practices and helps improve your retention and exhalation, which is often the most difficult phase of pranayama practice for those who have an irregular practice and for beginners.