Abstract

Introduction and objectives:A device called FeelBreathe (R) (FB) has been designed, developed and patented for inspiratory muscle training (IMT). In order to examine the effects of FB on lung ventilation and gas exchange during exercise, 27 trained male healthy volunteers (age: 32.5 +/- 7.2 years) were measured. Methods: Maximum static inspiratory pressure (Pl(max)) and spirometry to determine lung capacity were measured at baseline. We continued with an incremental cycloergometer to determine the VO2 peak. Three days later, each subject performed randomly three identical submaximal cycloergometer tests at 50% between ventilatory thresholds under three different breathing conditions: a) oronasal breathing (ONB), b) nasal breathing (NB) and c) nasal breathing through the FB. Results: FB trial showed lower minute ventilation (VE) and breathing frequency (BF) than NB, which had lower BE, but similar VE than ONB (p 0.001). Despite this, FB had similar values of VO2, respiratory exchange ratio (ER), heart rate (HR) and peripheral capillary oxygen saturation (SpO(2)) compared to NB and ONB. The latter can occur partly due to increased tidal volume (VT) and expiration time (Tex) in FB until same level than NB, which were in both trials 15% and 14% respectively higher than ONB (p 0.001). The percentage of inspiration time (Ti/Tot) was 7% greater in FB compared to NB and ONB (p 0.001). Increased end-tidal pressure of CO2,(PETCO2) and reduced end-tidal pressure of O2 (PETO2) and fraction of O-2 expiration (FEO2) were found only in FB. Conclusions: FeelBreathe is a new nasal restriction device that stimulates the inspiratory muscles to produce a breathing pattern more efficiency during exercise in well-trained humans.