The ins and outs of breath holding: simple demonstrations of complex respiratory physiology.
The physiology of breath holding is complex, and voluntary breath-hold duration is affected by many factors, including practice, psychology, respiratory chemoreflexes, and lung stretch. In this activity, we outline a number of simple laboratory activities or classroom demonstrations that illustrate the complexity of the integrative physiology behind breath-hold duration. These activities require minimal equipment and are easily adapted to small-group demonstrations or a larger-group inquiry format where students can design a protocol and collect and analyze data from their classmates. Specifically, breath-hold duration is measured during a number of maneuvers, including after end expiration, end inspiration, voluntary prior hyperventilation, and inspired hyperoxia. Further activities illustrate the potential contribution of chemoreflexes through rebreathing and repeated rebreathing after a maximum breath hold. The outcome measures resulting from each intervention are easily visualized and plotted and can comprise a comprehensive data set to illustrate and discuss complex and integrated cardiorespiratory physiology.
Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada; and.
Rachel J
RJ
Skow
Faculty of Science and Technology, Mount Royal University, Calgary, Alberta, Canada.
Trevor A
TA
Day
Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada; and.
Jonathan E
JE
Fuller
Faculty of Science and Technology, Mount Royal University, Calgary, Alberta, Canada.
Christina D
CD
Bruce
Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada; and craig.steinback@ualberta.ca.
Craig D
CD
Steinback
D001784:Blood Gas Analysis / Q000379:methods; D062485:Breath Holding; D002245:Carbon Dioxide / Q000097:blood; D004504:Education, Medical, Undergraduate / Q000379:methods; D004521:Educational Measurement; D005260:Female; D006801:Humans; D008297:Male; D010100:Oxygen / Q000097:blood; D010827:Physiology / Q000193:education*; D015656:Respiratory Mechanics / Q000502:physiology*; D012143:Respiratory Physiological Phenomena; D013997:Time Factors; D055815:Young Adult
D002245:Carbon Dioxide; D010100:Oxygen
Hering-Breuer reflex; carbon dioxide; chemoreflexes; feedback loops; oxygen