Rebuttal from Jean‐Paul Richalet

Richalet, Jean‐Paul

doi:10.1113/jp279426

Cited by 1 publication

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Whether normobaric and hypobaric hypoxia are equivalent and then interchangeable has been an intense source of scientific debate, particularly with regards to their impact on exercise performance and various physiological parameters. Systematic reviews and “points-counterpoints” discussions have however, not enable researchers to reach any consensus ( Girard et al, 2012 ; Millet et al, 2012a , b , 2013 ; Mounier and Brugniaux, 2012a , b ; Faiss et al, 2013 ; Debevec and Millet, 2014 ; Richard et al, 2014 ; Coppel et al, 2015 ; DiPasquale et al, 2016 ; Richalet, 2020a , b ). Discrepancy between studies can be attributable to many cofounding factors: Different degrees of hypoxia, themselves determined either by barometric pressure, inspired PO 2 , oxygen fraction; seasonal and geographical differences in barometric pressure; air temperature and humidity; additional environmental stressors such as cold exposure; duration of exposure; presence or not of exercise interventions, and if so different exercise protocols; characteristics of subjects; animal versus human studies.…”

Section: Skeletal Muscle Angio-adaptive Responses To Hypoxia: Do Normobaric and Hypobaric Conditions Differ?mentioning

confidence: 99%

Altitude, Exercise, and Skeletal Muscle Angio-Adaptive Responses to Hypoxia: A Complex Story

Lemieux

Birot

2021

Front. Physiol.

View full text Add to dashboard Cite

Hypoxia, defined as a reduced oxygen availability, can be observed in many tissues in response to various physiological and pathological conditions. As a hallmark of the altitude environment, ambient hypoxia results from a drop in the oxygen pressure in the atmosphere with elevation. A hypoxic stress can also occur at the cellular level when the oxygen supply through the local microcirculation cannot match the cells’ metabolic needs. This has been suggested in contracting skeletal myofibers during physical exercise. Regardless of its origin, ambient or exercise-induced, muscle hypoxia triggers complex angio-adaptive responses in the skeletal muscle tissue. These can result in the expression of a plethora of angio-adaptive molecules, ultimately leading to the growth, stabilization, or regression of muscle capillaries. This remarkable plasticity of the capillary network is referred to as angio-adaptation. It can alter the capillary-to-myofiber interface, which represent an important determinant of skeletal muscle function. These angio-adaptive molecules can also be released in the circulation as myokines to act on distant tissues. This review addresses the respective and combined potency of ambient hypoxia and exercise to generate a cellular hypoxic stress in skeletal muscle. The major skeletal muscle angio-adaptive responses to hypoxia so far described in this context will be discussed, including existing controversies in the field. Finally, this review will highlight the molecular complexity of the skeletal muscle angio-adaptive response to hypoxia and identify current gaps of knowledges in this field of exercise and environmental physiology.

show abstract