Men and women in hypoxia : the influence of tissue oxygenation on repeated-sprint ability

Thumbnail Image
Smith, Kurt
University of Lethbridge. Faculty of Arts and Science
Journal Title
Journal ISSN
Volume Title
This thesis examined the impact of oxygen (O2) availability on prefrontal cortex and muscle tissue oxygenation during repeated-sprint exercise (RSE) in men and women. Men and women matched for initial-sprint mechanical work performed during ten, 10-s sprints (30s of rest) in normoxia (21% FIO2) and acute hypoxia (13% FIO2). Mechanical work and arterial O2-saturation (SPO2) were obtained for every sprint. Oxy- and deoxygenated haemoglobin concentrations (O2Hb, HHb) were obtained via near-infrared spectroscopy. Hypoxia elicited lower SPO2 and work (14.8% & 7.4%, P < 0.05), larger (45.1%, P < 0.05) and earlier reductions in cortical oxygenation, and no differences between sexes. Cortical de-oxygenation and work decrement were strongly correlated (R2=0.85, P < 0.05). Muscle de-oxygenation was greater in men than women (67.3%, P < 0.05). These results show that O2 availability influences cortical oxygenation and performance equally in men and women, and suggest a more efficient muscle O2 uptake in women.
ix, 108 leaves : ill. ; 29 cm
Anoxemia , Oxygen -- Physiological effect , Oxygen in the body , Cerebral anoxia , Muscles -- Physiology , Sports -- Physiological aspects , Exercise -- Physiological aspects , Exercise tests , Athletes -- Physiology , Women athletes -- Physiology , Dissertations, Academic