Resources
Articles
2019 Review: Heat stress and fetal risk"...no study has ever reported the core temperature of a pregnant woman to exceed 38.0°C, 1.0°C lower than the critical maternal core temperature, when exercising in a warm bath (30°C) or during resting exposure to a hot and dry sauna (70°C; 15% RH) or immersion in a 40°C water bath for up to 20 min. Change in core temperature during exercise/heat exposure appears to decline with progressive pregnancy..."
"Only one study met the criteria for CEBM level I evidence, and there was especially limited evidence for water immersion exercise (grade C) and sauna or hot bath use (grade D). This means that recommendations may change with future research."
Historical and Anecdotal Evidence
Bruce Thompson's anecdotal experience
Textbook: Physical Therapy in Nursing Care - historical evidence including Spanish flu
Physiology
YouTube channel: Dr Roger Seheult's Coronavirus Pandemic Updates, Updates 44, 46 and 47 relate to hydrotherapy
Opinion Article by Marc Cohen, July 2020: Turning up the heat on COVID-19: heat as a therapeutic intervention
Nasal breathing and Nitric Oxide
Short article: Nasal breathing and nitric oxide
Science Paper: Weitzberg, E., Lundberg, J.: Humming Greatly Increases Nasal Nitric Oxide, Am J Respir Crit Care Med 166(2):144-145, 2002.
2019 Review: Heat stress and fetal risk"...no study has ever reported the core temperature of a pregnant woman to exceed 38.0°C, 1.0°C lower than the critical maternal core temperature, when exercising in a warm bath (30°C) or during resting exposure to a hot and dry sauna (70°C; 15% RH) or immersion in a 40°C water bath for up to 20 min. Change in core temperature during exercise/heat exposure appears to decline with progressive pregnancy..."
"Only one study met the criteria for CEBM level I evidence, and there was especially limited evidence for water immersion exercise (grade C) and sauna or hot bath use (grade D). This means that recommendations may change with future research."
Historical and Anecdotal Evidence
Bruce Thompson's anecdotal experience
Textbook: Physical Therapy in Nursing Care - historical evidence including Spanish flu
Physiology
YouTube channel: Dr Roger Seheult's Coronavirus Pandemic Updates, Updates 44, 46 and 47 relate to hydrotherapy
Opinion Article by Marc Cohen, July 2020: Turning up the heat on COVID-19: heat as a therapeutic intervention
Nasal breathing and Nitric Oxide
Short article: Nasal breathing and nitric oxide
Science Paper: Weitzberg, E., Lundberg, J.: Humming Greatly Increases Nasal Nitric Oxide, Am J Respir Crit Care Med 166(2):144-145, 2002.