Tim:

        I think you're on the right track....AFA your friend with the double hernia, if he'd been playing with the proper kind of body support (that is to say: pulling the back muscles DOWN AND IN and the abdominal muscles UP AND IN) he wouldn't have torn the muscles of the groin at all...

        Tears in those muscles occur with the old-fashioned idea of *pushing out against the belt*, which is counterproductive in many respects, since, besides the hernia potential, that technique also tends to enable the *valsalva effect* (or a tightening/closing of the upper chest and throat)....

        It's far better, imho, to cultivate as relaxed a playing style as possible, including the idea of *balancing* the trumpet on the left hand (which leaves the right hand free to finger the valves and apply shading via vibrato as needed since there isn't a deathgrip on the valves to impede the process); keeping a seal between the lips (to avoid the creation of resistance elsewhere in the system, such as in the throat(closing) or the teeth(closed), or even raising the tongue too high inside the back of the oral cavity, which can lead to *blackouts* when the force of air erupts up into the delicate nasal sinuses); and supporting and controlling the airstream with the muscles of the trunk of the body, rather than the extremities...

        All of this contributes to the concept of linear playing, which enables the player to play with a balanced, free sound in whatever register is required, and, incidentally, reduces the seafood incidence in performances...

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Take Care!
Jeannie