Physiological differences between fit and unfit college-age males during exercise in normobaric hypoxia
Year: 2013
Type: article
Abstract: Previous research suggests that physical activity may result in to decreases in arterial saturation (SaO2) and cerebral blood flow when exposed to a low oxygen environment between aerobically fit and unfit males. Purpose: The purpose of this study was to determine differences in SaO2, cerebral blood flow, minute ventilation (VE), and blood lactate between fit and unfit young males during exercise in hypoxia compared to normoxia. Methods: Apparently healthy college age males took part in two trials consisting of normobaric normoxia and normobaric hypoxia (12% oxygen). Fit (n = 3; VO 2max = 51.5 ml • kg-1 • min-1 ± 3.1) and Unfit (n = 3; VO2max = 34.4 ml • kg -1 • min-1 ± 5.6) males cycled at 50% of their altitude adjusted VO2max (-26% of normoxia VO2max) for one hour after a two-hour baseline. Results: SaO 2, cerebral blood flow, and RER were significantly decreased during hypoxia in all subjects (P < 0.05), but did not differ between groups. An interaction showed that Fit subjects had a higher SaO2 during exercise in hypoxia (P < 0.05). VE and lactate was greater during hypoxia (P < 0.05). The Fit group demonstrated a higher V E during exercise in hypoxia (P < 0.05). No differences in blood lactate were found between the two groups. Conclusion: The data suggests that when exposed to hypoxia aerobically unfit males may demonstrate decrements in oxygen utilization which may lead to decreases in physical activity and/or performance.
Author: Matthew V. Bliss
Institution: Kent State University
Language: English
Topic: High Altitude and Hypoxia
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2229399785