How to Train for Stamina

"I train my back with the with weights like insane pain. Crunch all the air out," he says of his breathing exercises. "And literally you only do for 30 repetitions, which again takes about maximum four and a half minutes." He does it every day for four minutes or every other day, two times a week. 'You never used before. I did 30 the first time. Do it for three days'