The Breath Sound Check and Exercise at or about the Ventilatory Threshold

Abstract

There is a scarcity of information on the control of exercise intensity using ventilation and/or breathing sounds. We have reported^{6, 7} that when a subject while jogging can “hear your breathing” that subject is at or near their Ventilatory Threshold (VT1). The VT1 has been described by Plowman and Smith¹⁵ as “the first breakpoint in volume expired per minute.” The use of heart rate and/or perceived exertion does not always indicate the metabolic intensity at which the subject is operating¹. There is evidence that exercising at the VT1 is beneficial for cardiac transplant patients¹², asthmatics¹⁶, diabetics¹³, obese subjects¹⁴, and young and older populations^{5, 10, 8}. At the exercise intensity of the VT1 cardiovascular and respiratory improvements occur. Measurement of aerobic power (VO₂ max) is often employed as an indicator of the effectiveness of an exercise program, however, significant increases in VT1 can occur with minimal changes in VO₂ max and can result in health benefits^{9, 10}.