Cold-induced vasodilation responses before and after exercise in normobaric normoxia and hypoxia

摘要

PurposeCold-induced vasodilation (CIVD) is known to protect humans against local cold injuries and improve manual dexterity. The current study examined the effects of metabolic heat production on cold-induced vasodilation responses in normobaric hypoxia and normoxia.MethodsTen participants immersed their non-dominant hand into 5 degrees C water for 15min. Minimum finger temperature (T-min), maximum finger temperature (T-max), onset time, amplitude, and peak time were measured before and after exercise under normoxia (21% O-2) and two levels of normobaric hypoxia (17% O-2 and 13% O-2).ResultsNeither T-min nor amplitude was affected by hypoxia. However, T-max was significantly decreased by hypoxia while reduction in onset time and peak time trended towards significance. T-min, T-max,T- and amplitude were significantly higher during post-exercise CIVD than pre-exercise CIVD.ConclusionThe CIVD response may be negatively affected by the introduction of hypoxia whereas metabolic heat production via exercise may counteract adverse effects of hypoxia and improve CIVD responses.