@The Nail, I apologize for the lateness of my reply.
I practiced Buteyko daily for several years. The usual progression is 4 practice sessions of 15-20 minutes each per day for the first month or until a CP of 60 seconds is achieved, and then many people scale back to twice a day practices. I have a good amount of illness in my history - a blue-in-the-face-from-coughing childhood is probably the high/low-light of it.
I therefore experimented, since Professor Buteyko said anywhere from 60 to 80 seconds is a good range, with keeping my CP higher, and found that around 75 seconds was good for me. More was a bit weird - my teacher has described it as going from fixing your broken commuter car to having a Ferrari to drive through the rush hour. A Ferrari isn't a good commuter car, and while a CP of more than 80 might be good for some high-level athletes, I didn't care for what it felt like.
My current practice is quite vigorous and if I do it more than a couple of times a week, my CP gets too high, so I do one vigorous practice and several others, or I do 2-3 vigorous sessions per week. Vigorous - I breath normally, exhale normally, hold my nose and close my mouth, and start with a relaxed walk which breaks into a jog and then a run and then a sprint, all while not breathing. I cover 150-200 meters in a bit over a minute this way.
The effects of Buteyko practice have been nothing short of life-changing for me. It is a meditative practice, and I am much calmer, have a much easier time concentrating and a much easier time relaxing in my life overall. And after taking asthma and allergy medicines around the clockm 365 days a year for several decades, I have been off them completely for several years and have, quite literally, never felt better.
@aciampa might wish to share his reactions to the practice. I was my honor and pleasure to teach Al as my private student, and he is now a teacher in our school.
-S-
