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Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice
Published on: March 15, 2019
Persistent suppression of resting energy expenditure after acute hypoxia
Kerstin M Oltmanns1, Hartmut Gehring, Sebastian Rudolf
1Department of Psychiatry, University of Luebeck, 23538 Luebeck, Germany. oltmanns@medinf.mu-luebeck.de
Metabolism: Clinical and Experimental
|April 25, 2006
Summary
Acute hypoxia temporarily reduces resting energy expenditure (REE) in healthy men. This metabolic adaptation persists for at least 150 minutes after oxygen levels normalize, impacting energy balance.
Area of Science:
- Human physiology
- Metabolic studies
- Environmental medicine
Background:
- Resting energy expenditure (REE) is influenced by ambient oxygen levels.
- Acute hypoxia in healthy individuals causes a temporary drop in REE.
- The persistent effects of hypoxia on REE after exposure have not been fully investigated.
Purpose of the Study:
- To investigate the persistent effects of acute hypoxia on resting energy expenditure (REE) in healthy men.
- To determine if REE remains altered after hypoxia has ended, independent of confounding factors.
- To explore potential underlying mechanisms, including hormonal and metabolic changes.
Main Methods:
- A double-blind, crossover study involving 13 healthy men.
- 30 minutes of induced hypoxia (oxygen saturation to 75%) versus normoxic control (96%).
- Indirect calorimetry performed at baseline and 150 minutes post-hypoxia, with controlled glucose levels and monitored lactate, catecholamines, and thyroid hormones.
Main Results:
- Resting energy expenditure (REE) was significantly decreased 150 minutes after hypoxia compared to normoxic conditions (P=.037).
- The respiratory quotient remained stable, indicating no significant change in substrate utilization.
- Plasma lactate, catecholamine levels, and thyroid hormone activity were unchanged, ruling out these as mediators of the persistent REE decrease.
Conclusions:
- Acute hypoxia induces a persistent decrease in resting energy expenditure (REE) that lasts for at least 150 minutes after exposure.
- This prolonged reduction in energy metabolism suggests an adaptive response to hypoxia.
- The findings highlight REE changes as a potential contributing factor in diseases characterized by disturbed energy metabolism.
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