There are many different approaches to breathing in the world of singing and much of the information can appear contradictory e.g. some teachers recommend you breath through the nose and others through the mouth. Having researched deeply in this area I favour a natural approach that enhances peoples everyday breathing. I therefore employ techniques from Chi kung and yoga which are often simpler yet far more effective than the usual classical singing breathing exercises. This is because one of the mistakes I often notice with those who have had classical training and then want to sing e.g. soul is that they are constantly checking and focusing on their diaphragm etc. rather than the song - it therefore lacks soul.
Just like an athlete the singer benefits from being relaxed yet alert,with a good posture and energized spine. Here the alexander technique which promotes efficient use of the posture can be very useful. I also teach people exercises from yoga and chi kung to help open the structure of the body and achieve the most efficient use of energy