Borgia, J. F., et al. Some Physiological Observations on French Horn Musicians. Journal of Occupational Medicine 17, no. 11 (November 1975): 696-701.
The cardiovascular changes observed secondary to horn playing are studied to explore the hypothesis that the intense respiratory strain used in horn playing may cause occasional loss of consciousness. This strain is sustained intra-oral pressure which exceeds that used for clinical observation in the Valsalva maneuver. This supports Tucker's demonstration that young brass players are exceedingly disposed to cardiac arrhythmias. This study dispenses a uniform musical exercise to a cross-section of French horn players to determine if adaptive changes have arisen that contribute resistance to the stress of performance on brass instruments.