Integrative crosstalk between hypoxia and the cold: Old data and new opportunities

Abstract

Cold stress and hypoxia have been the subject of research for decades; however, humans often encounter these stressors together, such as in the alpine environment. Therefore, this review summarizes previous data with respect to the influence of hypoxia on thermoregulatory and cardiovascular control in the cold and presents new ideas for the future. Altogether, little to no evidence is available on the integrative and adaptive mechanisms by which the human body regulates heat conservation, oxygen delivery and maintenance of blood pressure.

Practicing Sport in Cold Environments: Practical Recommendations to Improve Sport Performance and Reduce Negative Health Outcomes

“…This reduction in time to exhaustion is likely related to crosstalk between the highly integrative, overlapping mechanisms which control heat conservation, preferential oxygen delivery and blood pressure maintenance in cold, hypoxic conditions even evident at rest [10]. For further information on the combined effects of cold exposure and hypoxia, the interested reader is referred to Mugele et al (2021) [10] In addition to force generation, exposure to cold environments and cooling of large parts of the lower extremities may also negatively affect postural control and dynamic balance [75,76]. Such detrimental effects may still be apparent when exposures to cold air are repeatedly performed [75].…”

Hypoxia research: to control or not to control? That is the question

“…These behavioural factors will in turn affect the rate of shivering and metabolic heat production (thermogenesis), and should therefore not be ignored during hypoxia research (Mugele et al . 2021).…”

“…Cold stress most notably increases mean arterial pressure (Mugele et al . 2021). Vasoconstriction in the peripheral, visceral, and cerebrovascular beds promotes central hypervolaemia, thereby increasing cardiac preload and afterload.…”

“…With the addition of hypoxia, a conflict between maintaining oxygen delivery to vascular beds (hypoxia‐induced vasodilatation) and altering skin blood flow to conserve heat and energy occurs (Mugele et al . 2021).…”

Experimental Physiology special issue: Extreme environmental physiology

“…Unfortunately, the inclination to pigeon‐hole science and scientists has meant that, with the exception of heat and humidity, these combinations of environmental stresses have received relatively little attention (23 such studies between 1948 and 2012; Tipton, 2012). Thankfully, that is changing, and in the present Special Issue we have a review that examines the influence of hypoxia on thermoregulatory and cardiovascular control in the cold (Mugele, Oliver, Gagnon, & Lawley, 2021), and a paper reporting the effect of normobaric hypoxia on the critical environmental limits for thermal balance during exercise heat stress (Coombs, Cramer, Ravanelli, Imbeault, & Jay, 2021).…”