We tested a PEEP (4.2 cmH2O) mouthpiece (PMP) on maximal cycling performance in healthy adults. Experiment-1, PMP vs. non-PMP mouthpiece (CON) [n =9 (5), Age=302yr]; Experiment-2, PMP vs. no mouthpiece (NMP) [n=10 (7), Age=271yr]. At timepoint 1 in both experiments (mouthpiece condition randomized) subjects performed graded cycling testing (GXT) (Corival cycle ergometer) to determine V O2peak (mlkgmin -1), O2pulse (mlO2bt -1), GXT endurance time (GXT-T(s)), and V O2(mlkgmin -1)-at-ventilatory-threshold ( V O2 @VT). At timepoint 2 72h later, subjects completed a ventilatory-threshold-endurance-ride [VTER(s)] timed to exhaustion at V O2 @VT power (W). One week later at timepoints 3 and 4 (time-of-day controlled), subjects repeated testing protocols under the alternate mouthpiece condition. Selected results (paired T-test, p<0.05): Experiment 1 PMP vs. CON, respectively: V O2peak=45.22.4 vs. 42.42.3 p<0.05; V O2@VT=33.72.0 vs. 32.31.6; GXT-TTE=521.773.4 vs. 495.372.8 (p<0.05); VTER=846.2166.0 vs. 743.1124.7; O2pulse=24.51.4 vs. 23.11.3 (p<0.05). Experiment 2 PMP vs. NMP, respectively: V O2peak=43.31.6 vs. 41.71.6 (p<0.05); V O2@VT=31.11.2 vs. 29.11.3 (p<0.05); GXT-TTE=511.749.6 vs. 486.449.6 (p<0.05); VTER 872.4134.0 vs. 792.9122.4; O2pulse=24.10.9 vs. 23.40.9 (p<0.05). Results demonstrate that the PMP conferred a significant performance benefit to cyclists completing high intensity cycling exercise.
