The effects of nose-breathing-only training on physiological parameters related to running performance

Abstract

Background: At rest, nose breathing has been proposed to be superior to mouth breathing due to the warming, humidifying, and filtering capacities of the nose and related structures. Little is known about the capacity for humans to practice nose breathing during physical activity. Objective: The effects of a 6-week nose breathing running program on running performance, breath hold endurance, resting and exercising physiological variables, and the subjective experience, were investigated in a trained runner previously unaccustomed to nose breathing. Methods: A single (n=1) male participant completed a 6-week running training program, during which all running efforts were completed while the participant breathed only through the nose. Objective measures included: Breath hold tests (BHT), a graded exercise test to determine the highest intensity of running where a voluntary switching point between nose breathing and mouth breathing occurred (GXT), and regular breathing five-kilometre time trials (5kmTT) were conducted before, during, and after the 6-week running program. A daily journal described the subjective experience of each daily run, interval workout, and testing event which specifically looked to detail any dyspnea episodes which occurred. Results: Subjectively, the participant experienced frequent intense dyspnea in the early stages ofthe running program. Running pace during the first week of nose breathing (NB1) was significantly slower than the mouth breathing (MB) (M=259.75±2.72 vs. M=245.50±1.49 s•km-1,respectively. p=0.015). Pace was not significantly different from the MB pace in the following weeks except for nose breathing week 6 (NB6) which was significantly faster than MB(M=228.00±5.51 vs. M=245.50±1.49 s•km-1, respectively. p=0.041). Heart rate showed no significant changes at any point during the running program. The BHT improved by 34.1 s or77% between PRE and POST. The running speed during the GXT when the participant could no longer sustain nose breathing, increased by 23% between the PRE and MID testing and improved a further 1% between MID and POST. The 5kmTT showed a 77 s or 6.21% improvement between the PRE and POST running trials. Conclusion: In this case study, it was demonstrated that undertaking a running training program while nose breathing only, is feasible for a trained runner, and an effective method of training that yields improvement in 5km timetrial performance similar to reported results in the literature that did not restrict mode of breathing.