James Carter, Harry Carney, Joshua Redman Kenny G & Hans-Christian Dellinger. What do they all have in common?

Well, they all play or played saxophone. But what I mean is "Circular Breathing".
Ever since hearing Harry Carney play "Sophisticated Lady" with Duke Ellington, I've been fascinated by the ability to sustain a tone for what seems endless time. I was baffled. When does he breath? He must have lungs the size of zeppelins. Well, the answer is not in how much air the lungs can hold but in mastering circular breathing. The are umpteen websites on the subject, but I've asked Hans Christian Dellinger how he does it, and he explained it's breathing in while at the same time breathing out. To try this you can blow your cheeks up and using just the air in your mouth, slowly breath out whilst breathing in and out through the nose.
If you listen carefully, you will notice how all the people above have perfected this technique to a fine art. It's not easy. I even read once that Kenny G. holds the world record for playing the longest note on the saxophone without taking a breath. I think it was over an hour!