Advertisement

The Effect of Two Different Intermittent Hypoxia Protocols on Ventilatory Responses to Hypoxia and Carbon Dioxide at Rest

  • Michael Koehle
  • William Sheel
  • William Milsom
  • Donald McKenzie
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 605)

Intermittent hypoxia (IH) consists of bouts of hypoxic exposure interspersed with normoxic intervals. The optimal IH regime for increasing the ventilatory response in humans is unknown, although in animals there is evidence that multiple short duration bouts of intermittent hypoxia (SDIH) provoke larger changes in chemosensitivity than longer duration bouts of intermittent hypoxia (LDIH). The purpose of this study was to compare responses to both hypercapnia and hypoxia between the two protocols. Methods: In a randomised crossover design, 10 healthy males underwent two 7-day poikilocapnic IH protocols. The LDIH protocol consisted of daily 60-minute exposures to normobaric 12% O2 (balance N2). The SDIH protocol comprised twelve 5-minute bouts of normobaric 12% O2, separated by 5-minute bouts of room air daily. We measured the isocapnic acute hypoxic ventilatory response (HVR), hypercapnic ventilatory response (HCVR) and CO2 threshold and sensitivity by the modified Read rebreathing technique. Pre-testing was performed immediately prior to intermittent hypoxic training. Follow-up testing occurred on the first day following IH and at 7 days after completion of IH. HVR testing was also performed on every day of the IH protocol prior to the hypoxic exposure.

Keywords

Intermittent Hypoxia Ventilatory Response Hypoxic Exposure Chronic Intermittent Hypoxia Normobaric Hypoxia 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Ainslie, P.N., Kolb, J.C., Ide, K. and Poulin, M.J. (2003) Effects of five nights of normobaric hypoxia on the ventilatory responses to acute hypoxia and hypercapnia. Respir. Physiol. Neurobiol. 138, 193–204.CrossRefPubMedGoogle Scholar
  2. Duffin, J., Mohan, R.M., Vasiliou, P., Stephenson, R. and Mahamed, S. (2000) A model of the chemoreflex control of breathing in humans: model parameters measurement. Respir. Physiol. 120, 13–26.CrossRefPubMedGoogle Scholar
  3. Foster, G.E., McKenzie, D.C., Milsom, W.K. and Sheel, A.W. (2005) Effects of two protocols of intermittent hypoxia on human ventilatory, cardiovascular and cerebral responses to hypoxia. J. Physiol. 567, 689–699.CrossRefPubMedGoogle Scholar
  4. Katayama, K., Sato, K., Matsuo, H., Hotta, N., Sun, Z., Ishida, K., Iwasaki, K. and Miyamura, M. (2005) Changes in ventilatory responses to hypercapnia and hypoxia after intermittent hypoxia in humans. Respir. Physiol. Neurobiol. 146, 55–65.CrossRefPubMedGoogle Scholar
  5. Katayama, K., Sato, Y., Morotome, Y., Shima, N., Ishida, K., Mori, S. and Miyamura, M. (2001) Intermittent hypoxia increases ventilation and SaO2 during hypoxic exercise and hypoxic chemosensitivity. J. Appl. Physiol. 90, 1431–1440.PubMedGoogle Scholar
  6. Katayama, K., Sato, Y., Shima, N., Qiu, J.C., Ishida, K., Mori, S. and Miyamura, M. (2002) Enhanced chemosensitivity after intermittent hypoxic exposure does not affect exercise ventilation at sea level. Eur. J. Appl. Physiol. 87, 187–191.CrossRefPubMedGoogle Scholar
  7. Koehle, M.S., Foster, G.E., McKenzie, D.C. and Sheel, A.W. (2005) Repeated measurement of hypoxic ventilatory response as an intermittent hypoxic stimulus. Respir. Physiol. Neurobiol. 145, 33–39.CrossRefPubMedGoogle Scholar
  8. Mahamed, S. and Duffin, J. (2001) Repeated hypoxic exposures change respiratory chemoreflex control in humans. J. Physiol. 534, 595–603.CrossRefPubMedGoogle Scholar
  9. Mateika, J.H., Mendello, C., Obeid, D. and Badr, M.S. (2004) Peripheral chemoreflex responsiveness is increased at elevated levels of carbon dioxide after episodic hypoxia in awake humans. J. Appl. Physiol. 96, 1197–1205.CrossRefPubMedGoogle Scholar
  10. Peng, Y.J. and Prabhakar, N.R. (2004) Effect of two paradigms of chronic intermittent hypoxia on carotid body sensory activity. J. Appl. Physiol. 96, 1236–1242.CrossRefPubMedGoogle Scholar

Copyright information

© Springer 2008

Authors and Affiliations

  • Michael Koehle
  • William Sheel
  • William Milsom
  • Donald McKenzie

There are no affiliations available

Personalised recommendations