This case study investigated the effect of restricting breathing to the nasopharynx versus the oropharynx on the ability to perform maximal and high level steady state running in a highly trained triathlete who previously adapted himself to nasal only breathing during exercise as a means of inhibiting exercise-induced bronchospasm (EIB). The subject was tested using a maximal graded treadmill protocol (GXT) to voluntary exhaustion followed 10 minutes later by a 6 minute steady state treadmill protocol (SS) at 85% of the previously achieved maximal velocity in both breathing conditions. Oxygen uptake was measured via indirect calorimetry and 1 second forced expiratory volumes (FEV1) were measured with spirometry. In the GXT trials the subject produced a time to exhaustion (TE) of 6:24, a maximal oxygen consumption (VO2max) of 3.92 L/min. and a velocity at VO2max (VVO2max) of 9.7 mph while breathing only through the nasopharynx (NB). While breathing only through the oropharynx (OB) he produced a TE of 6:15, a VO2max of 3.80 L/min. and a VVO2max of 9.7 mph.. During the 6 minute SS trials running at 8.0 mph, his mean oxygen consumption was 4.16 L/min. in NB and 3.99 L/min. in OB. The subject experienced a 17% reduction in FEV1 (Pre = 5.03 L/sec., Post = 4.17 L/sec.) following the OB GXT not seen following the NB GXT. This case study confirms the ability of a highly trained competitive triathlete to adapt to breathing restricted to the nasopharynx during running at both a maximal effort and a subsequent high level steady state effort without a loss in performance or peak aerobic capacity, as a means of inhibiting EIB.
© Copyright 2016 Journal of Sport and Human Performance. Liberty University. Alle Rechte vorbehalten.