An acute exposure to intermittent negative airway pressure elicits respiratory long-term facilitation in awake humans

Research output: Contribution to journalArticlepeer-review


  • Harry Griffin
  • Shoug Yousef Y Al Humoud
  • Joshua Benson
  • Brendan Cooper

External organisations

  • Dept of Lung Function and Sleep, University Hospital Birmingham, Birmingham, UK.
  • School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham


BACKGROUND: A sustained elevation in respiratory drive following removal of the inducing stimulus is known as respiratory long-term facilitation (rLTF). We investigated whether an acute exposure to intermittent negative airway pressure (INAP) elicits rLTF in humans.

METHOD: 13 healthy males (20.9 ± 2.8 years) undertook two trials (INAP and Control). In the INAP trial participants were exposed to one hour of 30-second episodes of breathing against negative pressure (-10 cmH2O) interspersed by 60-second intervals of breathing at atmospheric pressure. In the Control trial participants breathed at atmospheric pressure for one hour. Ventilation following INAP (recovery phase) was compared to that during baseline.

RESULTS: Ventilation increased from baseline to recovery in the INAP trial (14.9 ± 0.9 vs 19.1 ± 0.7 L/min, P = 0.002). This increase was significantly greater than the equivalent during the Control trial (P = 0.019). Data shown as mean ± SEM.

CONCLUSION: In this study INAP elicited rLTF in awake, healthy humans. Further research is required to investigate the responsible mechanisms.


Original languageEnglish
Pages (from-to)20-26
Number of pages7
JournalRespiratory physiology & neurobiology
Early online date6 Jun 2019
Publication statusPublished - 1 Sep 2019


  • Intermittent negative airway pressure, Long-term facilitation