Similar results for face mask versus mouthpiece during incremental exercise to exhaustion

Investigations in the 1990s evaluated the influence of breathing assemblies on respiratory variables at rest and during exercise; however, research on new models of breathing assemblies is lacking. This study compared metabolic gas analysis data from a mouthpiece with a noseclip (MOUTH) and a face mask (MASK). Volunteers (7 males, 7 females; 25.1 +/- 2.7 years) completed two maximal treadmill tests within 1 week, one MOUTH and one MASK, in random order. The difference in maximal oxygen consumption (VO2max) between MOUTH (52.7 +/- 11.3ml center dot kg(-1)center dot min(-1)) and MASK (52.2 +/- 11.7ml center dot kg(-1)center dot min(-1)) was not significant (P=0.53). Likewise, the mean MOUTH-MASK differences in minute ventilation (V-E), fraction of expired oxygen (FEO2) and carbon dioxide (FECO2), respiration rate (RR), tidal volume (V-t), heart rate (HR), and rating of perceived exertion (RPE) at maximal and submaximal intensities were not significant (P>0.05). Furthermore, there was no systematic bias in the error scores (r=-0.13, P=0.66), and 12 of the 14 participants had a VO2max difference of <= 3ml center dot kg(-1)center dot min(-1) between conditions. Finally, there was no clear participant preference for using the MOUTH or MASK. Selection of MOUTH or MASK will not affect the participant's gas exchange or breathing patterns.