Related Experiment Video
Updated: Aug 5, 2025
Delivery of In Vivo Acute Intermittent Hypoxia in Neonatal Rodents to Prime Subventricular Zone-derived Neural Progenitor Cell Cultures
Published on: November 2, 2015
Ventilatory Pattern Influences Tolerance to Normobaric Hypoxia in Healthy Adults
Inés Albertus-Cámara1, Cristina Rochel-Vera1, Jose-Luis Lomas-Albaladejo1
1Research Group of Physical Exercise and Human Performance, Mare Nostrum Campus, University of Murcia, 30100 Murcia, Spain.
Introduction:
Tolerance to breathing in conditions with a decreased oxygen ratio is subject-specific. A normobaric hypoxia tolerance test (NHTT) is performed to assess the ability of each individual, as this may be influenced by genetic or personal factors such as age or gender. The aim of this study is to test the influence of deep breathing on hypoxia tolerance time.
Material And Methods:
A total of 45 subjects (21 parachutists and 24 students) performed two NHTTs at 5050 m altitude (iAltitude). Arterial (SatO2) and muscle (SmO2) oxygen saturation were monitored with the Humon Hex® device. The first NHTT was performed with free breathing, without any instructions; and the second NHTT was performed with wide, slow, diaphragmatic breathing. The NHTT was terminated at the end of 10 min or when a value of less than 83% was obtained.
Results:
The first NHTT was completed by 38.1% of parachutist and 33.3% of students while the second NHTT was completed by 85.7% and 75%, respectively. In the second NHTT, both parachutists and students had a significantly (p = 0.001) longer duration compared to the first NHTT. SmO2 and SatO2 values also increased significantly (p < 0.001) in both groups (p < 0.05).
Conclusion:
Performing controlled diaphragmatic breathing is successful in increasing hypoxia tolerance time and/or SatO2 values.
Related Concept Videos
01:23Physiological Control of Respiration
Breathing, a seemingly passive process, is regulated by the respiratory center in the brainstem. This center coordinates the involuntary control of respirations, which means it occurs without conscious effort, ensuring a smooth and uninterrupted pattern.
Regulation of Ventilation
The body maintains ventilation by monitoring levels of carbon dioxide (CO2), oxygen (O2), and hydrogen ion concentration (pH) in the arterial blood. Among these factors, the level of CO2 plays a crucial...
01:30Alterations in Respiration II
In Biot's breathing, the respiratory rate and depth are irregular, alternating between periods of deep gasping and apnea. Common causes...
01:25Hyperpnea and Hyperventilation
01:24Factors Affecting Respiration
01:31Chemical Factors Affecting Respiration Centers
CO2 has a potent influence on respiration and is strictly regulated....
01:19Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...