The study determined the physiological changes of Heart Rate (HR) and Blood-Volume-Pressure (BVP) as bar note increase in male a singer vs. time (sec.) over a total recording time of a 6 min 28 sec pre-rehearsed piece: Von den Striken meinen Sünden (‘From the Shackles of my Sins’), St. John’s Passion No. 7 VS, p. 33j. The HR baseline recording of (105.94±14.27 bpm) and BVP (8.36 ± 2.42 mV) were higher than known basal readings in a 70-kg man. Possibly the expectation of the commencement of the singing episode predominated. Block changes II – bars 27, 28 & 37 (mostly sung well); II – bars 39, 47, 48 & 57 (some errors); III – bars 70 & 76 (shortness of breath); and IV – at 335 sec. from the start of the piano passage to the end and applause at 340 sec]. In block I, presumably the limbic and medullary pathways due to singing well, lowered HR to 68.98±14.93 bpm at bar 28. In block I, the BVP was signifi cantly (p<0.05) raised, suggesting a physiologically-mediated muscle contraction of the diaphragm and intercostal muscles requiring a greater blood fl ow for the delivery of oxygen as a part of mitochondrial ATP generation. In block II, the errors in singing resulted in HR recordings that did not diff er from each other. In block III, the singer was short of breath with a drop of HR to 98.20±26.42 bpm (bar 76), suggesting a time-point just prior to the commencement of inspiration (or the start of peak inspiratory capacity). In block IV, the HR dropped from the end of the piano passage (120.03±16.94 bpm vs. baseline of 105.94±14.27 bpm) until the applause (92.03±14.01 bpm). An expert singer may be trained to cope with stress from singing a diffi cult piece of music