Effect of Intermittent Normobaric Hypoxia on Executive Functions

Effect of Intermittent Normobaric Hypoxia on Executive Functions Assessed With Different Cognitive Tests in Healthy Young Subjects

The main objective of this study was to analyze the effects of an intermittent normobaric hypoxia session on executive functions assessed with different cognitive tests given to healthy young subjects. Twenty-seven healthy volunteers were divided into an experimental group (EG; n=13) and a control group (CG; n=14). The EG performed the 'Odd One Out', 'Double Trouble' and 'Monkey Ladder' tests before and after the hypoxia tolerance session (12%, 4400 m) with the iAltitude simulator. The CG completed the same tests without hypoxia exposure.

Study Overview

• Status: Completed
• Conditions: Executive Function (Cognition); Normobaric Hypoxia
• Intervention / Treatment: Device: Intermittent normobaric hypoxia; Other: Normoxia

Detailed Description

The main objective of this study will be to analyze the effects of an intermittent normobaric hypoxia session on executive functions, assessed using different cognitive tests administered to healthy young subjects. A total of 27 healthy volunteers will be divided into two groups: an experimental group (EG; n=13) and a control group (CG; n=14).

The experimental group will perform the 'Odd One Out', 'Double Trouble', and 'Monkey Ladder' tests immediately before and after a hypoxia tolerance session (12% oxygen, equivalent to 4400 meters) using the iAltitude simulator. The control group will complete the same tests under normoxic conditions, without exposure to hypoxia.

The primary outcomes will include changes in cognitive performance scores in the administered tests. The experimental group is expected to show improvements in the Double Trouble test scores following hypoxia exposure. The control group may also show changes in the Double Trouble and Odd One Out tests between the pre- and post-tests.

Secondary outcomes will include physiological variables such as oxygen saturation (SaO₂) and heart rate (HR), which will be monitored during the hypoxia session in the EG. Statistically significant changes in SaO₂ and HR are anticipated as a result of the hypoxic exposure.

This study aims to determine whether a single session of intermittent normobaric hypoxia can lead to selective improvements in executive functions, particularly sustained attention, without negatively affecting other cognitive domains.

• Study Type: Interventional
• Enrollment (Actual): 27
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Murcia, Spain
    • Universidad Católica San Antonio de Murcia
  • Guadalupe
    • Murcia, Guadalupe, Spain, 30107
      • Universidad Católica San Antonio de Murcia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Young people aged between 18 and 40 years old

Exclusion Criteria:

• Pregnancy
• Prior experience in hypoxia training
• Previous experience in executive function tests
• Personal or family history of cardiovascular diseases or chronic conditions
• Diagnosed cardiac disorders.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intermittent Hypoxia Group; Participants are exposed to a single session of intermittent normobaric hypoxia at 12% oxygen concentration (equivalent to 4400 m altitude) using the iAltitude simulator. Cognitive tests are performed before and after the hypoxia session.	Device: Intermittent normobaric hypoxia; Participants in the experimental group undergo a single session of intermittent normobaric hypoxia simulated by the iAltitude device. The session consists of breathing air with 12% oxygen concentration (equivalent to 4400 meters altitude) for a specified duration. Cognitive tests are administered before and after the hypoxia exposure to assess executive functions.
Other: No Hypoxia Group; Participants undergo the same cognitive tests without exposure to hypoxia, serving as the control condition.	Other: Normoxia; Participants undergo the same cognitive tests without exposure to hypoxia, serving as the control condition.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Double Trouble Test	Change in cognitive performance score on the Double Trouble test; higher scores indicate better executive function and attention control. Unit of Measure: Score (units on a scale)	Day 1
Monkey Ladder Test	Change in cognitive performance score on the Monkey Ladder test; higher scores indicate better visuospatial working memory. Unit of Measure: Score and Level.	Day 1
Odd One Out Test	Change in reasoning performance score on the Odd One Out test; higher scores indicate better problem-solving ability. Unit of Measure: Score and Level.	Day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Pressure	Average of systolic and diastolic blood pressure measured in mmHg	Day 1
Oxygen Saturation	Oxygen saturation automatically monitored and recorded by the iAltitude hypoxia simulation system. Unit of Measure: %	During intervention
Heart Rate	Heart rate automatically monitored and recorded by the iAltitude hypoxia simulation system. Unit of Measure: Beats per minute (bpm)	During intervention
Sociodemographic Questionnaire	To define individual characteristics of participants such as age and gender.	Pre-test

Collaborators and Investigators

• Sponsor: Universidad Católica San Antonio de Murcia
• Investigators: Principal Investigator: Raquel Vaquero Cristóbal, PhD, Universidad Católica San Antonio de Murcia

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2023
• Primary Completion (Actual): April 30, 2023
• Study Completion (Actual): December 1, 2024

Study Registration Dates

• First Submitted: May 24, 2025
• First Submitted That Met QC Criteria: June 16, 2025
• First Posted (Actual): June 18, 2025

Study Record Updates

• Last Update Posted (Actual): June 18, 2025
• Last Update Submitted That Met QC Criteria: June 16, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Signs and Symptoms, Respiratory; Hypoxia
• Other Study ID Numbers: 4145/2022

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to ethical and privacy considerations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No