I just started my comeback which is from 1978. I was studying Arturo Sandoval on you tube playing his typical super fast scales. So I decided to take a stab at it and I started playing the F scale up and down as fast as I could for 10 minutes non stop. When I stopped, my lips were untouched but after 5 to 10 minutes all the muscles in my face were killing me. This convinced me that it was a healthy exercise. Did anyone ever see this exercise used before? I never felt my muscles worked so much in my life.