I am not a doctor; however I have had some experience with eye problems. I had cataracts in both eyes and as a result had surgery. Playing correctly has not affected my eyes at all.

There have recently been questions regarding high playing and eye problems, high playing and ear problems and high playing and head pains. These ALL suggest the use of too much pressure to play. I do know that it is possible to cause a heart attack or even a stroke by using too much pressure to play. Let me explain about pressure.  Although mouthpiece pressure is the one that is normally brought up, there is also lip pressure and abdominal pressure. Stevens used 2 types of grips one to help break the habit of too much pressure and the one everyone is accustomed to seeing the Ferguson band use. Grabbing the bottom of the valve casing helps ( more mental than physical ) to transfer some horn weight to the lower lip. It has other benefits as well. ( again more mental than physical ). Stevens would have a player put his horn into playing position and then move it away from the lips until they separated from the mouthpiece. Then you lock the elbows in place. To play you had to push your face into the horn instead of the other way around. Well you will not push as hard this way you can't push as hard this way. Pressure causes lip separation, swelling ..... Besides it holds the notes in. ( Creates the pressure you feel in your head.)  A player can be more responsive if using a relaxed setup.  This concept is used and has been written about by a large number of players. Lip pressure is also not a sure way to the upper register. It is possible to apply enough pressure even without the mouthpiece to stop the air flow. (Again creating pressure in the head.) When any mouthpiece pressure is added then this bottleneck refuses to let your high notes out. (Yet more pressure in your head.) There are more high c players that could in a few weeks be super c players because of this extreme lip pressure than for any other reason. They are not letting the air escape and thereby holding the notes in.
(Worse than this for some who may be predisposed to heart trouble, high blood pressure or stroke all of this unneeded playing pressure could be deadly. Remember Louis Armstrong was told by his doctor to not play above high c. Jake was told to not play above a high Eb. They were tested by having bloodpressure readings made while they were playing.)

Now to abdominal pressure. Everyone is in agreement that when we breathe we should start at the bottom . Fill the lower part of the lungs and let then expand. What do we do with it next. Some players  put it under pressure at once. Others only pressurize higher notes. Either way we MUST turn it around. Holding the air in causes too many problems to list. So when you take a breath use it at once. The breathing cycle should be inhale, exhale. Not inhale, stop, exhale. Different players and teachers stress different methods of abdominal pressure. Some tense the muscles. Some tense the muscles and try to lift  Some push outward and others contract from front to back. They all have one thing in common. The muscle tension is BELOW the chest. For what it's worth I have heard of a couple of players who had gotten hernias by pushing out. One is a good friend of mine and a former student of both Jacoby and Shew. Neither taught this to him and neither told him to stop either.  My first lesson with Jake I was only allowed to play a simple lip slur from second line g to middle c. I was told that I would need to learn how to breathe and when to use support. He had me place my hand on my stomach and play the lip slur. I took a breath turned the air around and played a supported g-c lip slur. I was told not to use my abdominals on notes that low . He played a lip slur with my hand on his stomach low c-g-c-g- high c. I felt no tension at all until he went to high c. What I learned was that there is enough pressure being applied already to your  ribcage in all directions from the air to properly support low notes. If we think of letting a low g roll out of the bell of the horn rather than blowing it out the sound is very free. Likewise a low c might travel a few feet in front of us. A middle c would travel still farther.... 'Jake' advocated no abdominal pressure at all under middle c. This can not happen as our muscle system is always under some tension but he meant no extra intentional pressure. This left more strength in reserve for the upper register. The higher notes are to shoot out of the bell and drill a hole in the back wall of the concert hall. Was this simple lesson learned in an hour or a day? No it took a while to stop kicking in my abdominals until I got over middle c. Even then to learn the difference between  some pressure and a lot of pressure took more time. After all fourth space e does not need the kick high c does. We all know this but until we test ourselves by playing with our hand on our abdominals we may not be doing what we know.  Finally if you are experiencing any pain in the head (eyes,ears...) or chest when playing then please go to a doctor for a complete  hysical.
Check for high bloodpressure, congestive heart failure, and possible stroke conditions like clogged arteries.

'Pops'
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