First of all I want to apologize for using Antonio Maria Valsalvaâ€™s name, may he rest in peace, in the context that I mentioned. I was trying to get a point across as to how much the trumpet means to be so as not to â€œsound like an invasion from a battered violists forum.â€ Jeanne, is fainting not also a â€œblackoutâ€? I was talking about fainting which can be caused from VM. At least this is what my lung doctor has told me. VM comes from bearing DOWN but also from bearing UP with the abdominal muscles to a structure that prevents full passage of air under pressure and trumpet players have high pressure in their lungs. Using a manometer to measure VM can attest to this. In fact, if a manometer could be attached to a trumpet mpc, it would show that every trumpet player creates VM at some level or another. Many of you have just learned to live with it to whatever degree you may have. Presently, to me VM is a poison to my system. Also, I know what closing the throat means being also a singer and from studying singing in a music conservatory. This using the throat does not apply to me but may apply to others in trying â€œto control the air, rather than keeping the airflow free until it hits the lips.â€ I have trumpets and mpcs of all sizes and in terms of OVERBLOWING, this could very well be the case. What I was doing years ago to that volume, I can not do today. Some people are made stronger to play the trumpet and others are not. You should feel fortunate that you were made to be a strong trumpet player and I hope that you continue for many years to come. Thank you for your invitation and I hope that someone here will who was afraid to post and to mention that they play with the conditions (problems) that you mentioned will take your offer to get your help. You are a true asset to the trumpet profession.