Program Protocol for a Population That Works in Conditions of Hypobaric Hypoxia

June 1, 2026 updated by: Jorge Torres Mejías

Physical and Nutritional Exercise Program Protocol for the Improvement of the Health Determinants of a Population That Works in Conditions of Intermittent Hypobaric Hypoxia

The objective of this randomized, longitudinal, single-blind, two-group parallel clinical trial is to evaluate the effect of a physical exercise and nutritional protocol on the health determinants of workers performing their work shift under hypobaric hypoxia conditions at 2,950 meters above sea level (masl) and to determine whether these interventions contribute to improving their health.

For this study, initial assessments of body composition, physical fitness tests, gut microbiota analysis, blood inflammatory markers, and quality of life surveys will be conducted on all subjects during the first and last day of their work shift at 2,950 masl. Subsequently, they will be divided into two groups. Subjects in Group 1 (G1) will follow the same guided exercise protocol along with a nutritional plan designed by the research team. Those in Group 2 (G2) will undergo guided physical training for the seven days they are working under hypobaric hypoxia conditions. Finally, the results of the analyses between time 1 and time 2 will be compared, in addition to intra-group evaluations

Study Overview

Detailed Description

This study is an investigation that seeks to evaluate the effect of a physical exercise and nutritional protocol on the determinants of health (nutritional status and body composition, metabolic-inflammatory parameters, glucose profile, gut microbiome, physical condition, autonomic nervous system, and sleep patterns) of workers who perform their workday at an astronomical observatory under hypobaric hypoxia conditions between 2,950 and 5,050 meters above sea level. The objective of this intervention is to standardize both physical and nutritional recommendations for this type of worker under intermittent hypobaric hypoxia conditions.

The procedure will begin by incorporating personnel who meet the inclusion criteria: (being an employee contracted by the ALMA Observatory with more than one year of seniority, working in AOS or OSF sectors of the observatory, and not suffering from non-communicable diseases such as type 2 diabetes or hypertension). On the other hand, the exclusion criteria for this research are: people who use pacemakers, those who are temporarily stationed at the facilities, and pregnant women. Once the "n" of 11 subjects for each research group has been obtained, all participants will undergo a nutritional and body composition assessment by a registered dietitian. This assessment will utilize a multifrequency bioimpedance analysis (BIA) device, model INBODY 270S. Participants will be asked to come to the designated laboratory after fasting for 4 hours and removing as much clothing as possible, including shoes, socks, and any metal jewelry. The analysis will consist of weighing the participant in kilograms and measuring their height (SECA 700 scale). Subsequently, waist and hip circumferences will be measured using a SECA 201 ergonomic measuring tape. To complete the nutritional assessment, participants will be asked to step onto the BIA device barefoot, where they will place the hand electrodes and follow the evaluation instructions provided by the device. Subsequently, a Polar H10 elastic heart rate monitor will be fitted to the chest area and connected to the Polar Beat app for continuous heart rate monitoring. Along with this heart rate monitor, each participant will also have an Actigraph WG3XBT elastic heart rate monitor fitted to their hip area to measure the intensity of their movements. To determine the physical condition and estimate the VO2max of the subjects under study, all will undergo a Modified Queens College box test, in a 20 cm high box for a period of 3 minutes. Finally, a Freestyle Libre 2 Plus continuous glucose monitoring patch will be fitted to the left triceps. These individually fitted devices will continue to collect data for 14 consecutive days. Once the entire installation phase is complete, each participant will be given two sealed, sterilized plastic containers. In these containers, they must provide the research team with two small fecal samples (one on the day of arrival at the observatory and another on the last day of their stay). These samples will be processed in the laboratory set up for this purpose at the observatory using a QIAamp PowerFecal Pro DNA Kit. A DNA sample will be extracted following the kit's instructions, then frozen and transported to the University facilities. There, the samples will be processed using a DNA sequencing system. They will be stored in the buffer included with the aforementioned extraction kit and subsequently frozen in a special -20°C refrigerator at the GEMA laboratory for later analysis. The samples will then be analyzed using an Invitrogen Qubit fluorometer to quantify the concentration of extracted DNA. Subsequently, the samples will be analyzed using capillary electrophoresis on a Bioptic Fragment Analyzer™ (QSep 1). Following this, the libraries will be prepared according to the sequencer to be used, and sequencing will then begin on an Illumina MiSeq and/or Nanopore MinION platform (depending on the number of DNA samples extracted and the amount of data to be sequenced).

In addition, a trained paramedic will collect 5 ml of venous blood, which will be placed in polypropylene tubes with anticoagulant and centrifuged at 3000 rpm. The plasma and blood will then be sent refrigerated to the CEIMA laboratory at Arturo Prat University for analysis and quantification of inflammatory factors using the SOD Colorimeter Activity Kit and the GSH-PX Activity Kit, following the respective manufacturers' instructions.

Once the initial analyses are complete, the study subjects will be divided into two groups:

G1 (Intervention group with resistance training and nutritional supplementation) This group will undergo a resistance training program guided by a physical activity professional for three days during their work shift, along with a daily intake of a probiotic and prebiotic supplement for seven days. To this end, the maximum number of repetitions (1RM) that the individual can perform for each of the four muscle groups will be calculated at the beginning. Therefore, 3 sets of 10 repetitions each will be performed for the following muscle groups: 1. biceps, 2. quadriceps, 3. pectorals, and 4. gastrocnemius, at 50% of the previously calculated maximum repetition.

In addition, this group's diet will be supplemented with the administration of two "Karún Life" brand probiotic tablets for the seven days of the work shift.

G2 (Overload Physical Exercise Intervention Group) This group will undergo the same overload training program as the previous group under the same conditions mentioned above.

Study Type

Interventional

Enrollment (Estimated)

22

Phase

  • Early Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Antofagasta
      • San Pedro de Atacama, Antofagasta, Chile, 1410000
        • Observatorio ALMA

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Be an employee of the ALMA Observatory, Chile.
  • Reside in the AOS (5,000 m above sea level) or OSF (2,950 m above sea level) sectors.
  • Have more than one year of employment history.

Exclusion Criteria:

  • Individuals with pacemakers.
  • Individuals only temporarily residing in observatory areas located in the Antofagasta Region.
  • Pregnant women.
  • Individuals with metal implants.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Health Services Research
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia
All members of group G1 of "overload exercise intervention", an activity that will be carried out 3 times during the week, will have three data collection devices installed, which are: heart rate monitor belt on the chest, accelerometer on the right hip, and continuous glucose analyzer on the right triceps, which will carry out continuous data collection for 14 consecutive days. Along with this, this entire group will also undergo a battery of exams: body composition analysis, phase angle determination, fecal DNA extraction, venous blood sample and a Queens College physical box test, which will be carried out on day one, (at the beginning of the work shift) and later on day seven, (last day of the shift). Along with this, food surveys on consumption trends and 24-hour counts will be carried out. Similarly, a Pittsburgh survey and the SF36 V2 survey will be applied to the entire population.
On the first day of sampling, muscle strength will be evaluated using arm and back dynamometry. Along with this, "the maximum repetition" (1RM) of the pectoral, quadriceps, biceps and gastrocnemius muscle groups will be determined, with their values recorded on the record. Subsequently, an exercise protocol will be carried out during day 2-4-6 of the work day, using eccentric muscle contraction exercises, with 50% of the maximum weight achieved in the initial tests, in the same muscle groups previously evaluated, through 3 series with 10 repetitions each. ending the intervention with a new dynamometry evaluation of the arms, back and MRI in these muscle groups.
Other Names:
  • physical exercise, overload exercise, exercises under hypobaric hypoxia conditions
Determination of body composition and phase angle in both intervention groups (G1 and G2), during day one of the beginning of the work shift and the last day, both under conditions of intermittent hypobaric hypoxia. For which, the subjects will be placed with as little clothing as possible, without any metal on the body, with bare feet on the InBody Bioimpedancemeter, Model: 270S., with which fat mass, fat-free mass, total body water, intracellular water, extracellular water and phase angle will be calculated.
Other Names:
  • Body Composition
  • fat mass
  • free fat mass
  • Bioimpedanciómetry
A heart rate monitor belt, POLAR brand, model H10, will be installed on all subjects in both groups, for 14 continuous days (seven days in conditions of hypobaric hypoxia and 7 days in normobaric conditions), equipment that will remain connected to the accelerometer that the participants will have, in order to record their heart rate along with the intensity of movement.
On the first day after the start of the work shift, a FreeStyle brand continuous glucose measurement patch will be installed in the area of the right triceps, which will be removed on the 14th (after the return of a new work shift), with which it is expected to know the glucose curves of people who perform work under conditions of intermittent hypobaric hypoxia between 2950 meters above sea level and 5050 meters above sea level.
Other Names:
  • glicemias continua
  • monitor de glicemia continua
A small sample of feces will be requested from each individual on day 1 at the start of the work shift and on day 7 at the end of the shift. Bacterial DNA will be extracted from these samples according to the manufacturer's protocol (QIAGEN_QIAamp PowerFecal Pro DNA Kit), which will be frozen to be sent to the GEMA laboratory of the Catholic University of Maule, where they will be sequenced in a Bioptic Fragment Analyzer processor (QSep 1).
Other Names:
  • Gut microbioma
On the first day of the start of the work shift, an elastic belt with an Actigraph brand accelerometer, model wgt3x-bt, will be installed, which will be attached to the body on the right hip of each subject under study. This device will be removed on the 14th day of use, with which it is expected to quantify the intensity of the subject's movement, both during their work days and days of rest (between 2950 meters above sea level and 5050 meters above sea level).
Other Names:
  • energy expenditure
  • Accelerometry
  • moviment intensity
A private survey will be carried out with each of the subjects being evaluated, using a survey to determine the quality of sleep of each person in conditions of intermittent hypobaric hypoxia called the Pittsburg Scale, an activity that will be carried out on a single occasion, during the work shift.
Other Names:
  • Cuestionario Pittsburg
Like the other surveys, we will use the SF32 V2 survey to develop the level of quality of life of each evaluated subject. This survey will be carried out privately, with an ONLINE questionnaire only once during the work shift.
Other Names:
  • Quality of life
During the first day of stay in conditions of hypobaric hypoxia, taking advantage of the H10 heart rate monitor installed in each subject together with the KUBIOS HRV application and an OMROM blood pressure meter, the evaluation of cardiac variability will be carried out, an activity that will be carried out in the clinic adapted for this work, for which, a time outside of work will be organized, during a rest time, (due to the protocol of the test). This evaluation is secondary to the study
Other Names:
  • Variabilidad Cardiaca
During the initial physical evaluations, you will undergo a physical test called the modified Queens Box, (in a 20 cm high box with a test duration of 3 minutes), in which the person must step up to the box and down from it in pulses of 96 per minute for men and 88 for women. The pulses obtained by the subject evaluated using the installed Polar H10 heart rate monitor will be recorded on a record at the end of the test, at minute 1, 2 and 3 once the test is finished.
During a day different from the initial evaluations, two personal surveys related to diet will be carried out on each study subject, which will be carried out by a qualified nutritionist professional. These surveys will provide valuable information on the eating habits of the study subjects during their working hours under conditions of hypobaric hypoxia and during their rest days.
Other Names:
  • consumer trend survey
  • 24-hour recall survey
Experimental: Group undergoing resistance training plus probiotic intake.
Arm Description: Group G2 of "overload exercise intervention and probiotic intake" will receive a dose of two daily tablets of Karún Life probiotics. Along with this, three data collection devices will be installed: a heart rate monitor belt on the chest, an accelerometer on the right hip, and a continuous glucose analyzer on the right triceps, which will carry out continuous data collection for 14 consecutive days. Along with this, this entire group will also undergo a battery of tests: body composition analysis, phase angle determination, fecal DNA extraction, venous blood sample and a Queens College physical box test, which will be carried out on day one, (at the beginning of the work shift) and later on day seven, (last day of the shift). Along with this, food surveys on consumption trends and 24-hour counts will be carried out. Similarly, a Pittsburgh survey and the SF36 V2 survey will be applied to the entire population.
On the first day of sampling, muscle strength will be evaluated using arm and back dynamometry. Along with this, "the maximum repetition" (1RM) of the pectoral, quadriceps, biceps and gastrocnemius muscle groups will be determined, with their values recorded on the record. Subsequently, an exercise protocol will be carried out during day 2-4-6 of the work day, using eccentric muscle contraction exercises, with 50% of the maximum weight achieved in the initial tests, in the same muscle groups previously evaluated, through 3 series with 10 repetitions each. ending the intervention with a new dynamometry evaluation of the arms, back and MRI in these muscle groups.
Other Names:
  • physical exercise, overload exercise, exercises under hypobaric hypoxia conditions
Determination of body composition and phase angle in both intervention groups (G1 and G2), during day one of the beginning of the work shift and the last day, both under conditions of intermittent hypobaric hypoxia. For which, the subjects will be placed with as little clothing as possible, without any metal on the body, with bare feet on the InBody Bioimpedancemeter, Model: 270S., with which fat mass, fat-free mass, total body water, intracellular water, extracellular water and phase angle will be calculated.
Other Names:
  • Body Composition
  • fat mass
  • free fat mass
  • Bioimpedanciómetry
A heart rate monitor belt, POLAR brand, model H10, will be installed on all subjects in both groups, for 14 continuous days (seven days in conditions of hypobaric hypoxia and 7 days in normobaric conditions), equipment that will remain connected to the accelerometer that the participants will have, in order to record their heart rate along with the intensity of movement.
On the first day after the start of the work shift, a FreeStyle brand continuous glucose measurement patch will be installed in the area of the right triceps, which will be removed on the 14th (after the return of a new work shift), with which it is expected to know the glucose curves of people who perform work under conditions of intermittent hypobaric hypoxia between 2950 meters above sea level and 5050 meters above sea level.
Other Names:
  • glicemias continua
  • monitor de glicemia continua
A small sample of feces will be requested from each individual on day 1 at the start of the work shift and on day 7 at the end of the shift. Bacterial DNA will be extracted from these samples according to the manufacturer's protocol (QIAGEN_QIAamp PowerFecal Pro DNA Kit), which will be frozen to be sent to the GEMA laboratory of the Catholic University of Maule, where they will be sequenced in a Bioptic Fragment Analyzer processor (QSep 1).
Other Names:
  • Gut microbioma
On the first day of the start of the work shift, an elastic belt with an Actigraph brand accelerometer, model wgt3x-bt, will be installed, which will be attached to the body on the right hip of each subject under study. This device will be removed on the 14th day of use, with which it is expected to quantify the intensity of the subject's movement, both during their work days and days of rest (between 2950 meters above sea level and 5050 meters above sea level).
Other Names:
  • energy expenditure
  • Accelerometry
  • moviment intensity
A private survey will be carried out with each of the subjects being evaluated, using a survey to determine the quality of sleep of each person in conditions of intermittent hypobaric hypoxia called the Pittsburg Scale, an activity that will be carried out on a single occasion, during the work shift.
Other Names:
  • Cuestionario Pittsburg
Like the other surveys, we will use the SF32 V2 survey to develop the level of quality of life of each evaluated subject. This survey will be carried out privately, with an ONLINE questionnaire only once during the work shift.
Other Names:
  • Quality of life
During the first day of stay in conditions of hypobaric hypoxia, taking advantage of the H10 heart rate monitor installed in each subject together with the KUBIOS HRV application and an OMROM blood pressure meter, the evaluation of cardiac variability will be carried out, an activity that will be carried out in the clinic adapted for this work, for which, a time outside of work will be organized, during a rest time, (due to the protocol of the test). This evaluation is secondary to the study
Other Names:
  • Variabilidad Cardiaca
During the initial physical evaluations, you will undergo a physical test called the modified Queens Box, (in a 20 cm high box with a test duration of 3 minutes), in which the person must step up to the box and down from it in pulses of 96 per minute for men and 88 for women. The pulses obtained by the subject evaluated using the installed Polar H10 heart rate monitor will be recorded on a record at the end of the test, at minute 1, 2 and 3 once the test is finished.
During a day different from the initial evaluations, two personal surveys related to diet will be carried out on each study subject, which will be carried out by a qualified nutritionist professional. These surveys will provide valuable information on the eating habits of the study subjects during their working hours under conditions of hypobaric hypoxia and during their rest days.
Other Names:
  • consumer trend survey
  • 24-hour recall survey
The entire group will be supplemented with a known dose of 2 tablets daily of the probiotic "Karún Life" for 2 weeks (during the work week and the subsequent week of rest).
Other Names:
  • Gut Microbiota Under Hypobaric Hypoxia

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Aerobic Fitness, (ml/kg/min oxygen utilization)
Time Frame: day 1 and 7 of the work shift
A modified Queens College box test (20 centimeter box height for 3 minutes) will be performed. Men will perform the test at 90 pulses per minute, while women will perform the test at a speed of 88 pulses per minute, for 3 minutes. Once the time is up, the participant's final pulse will be recorded using the POLAR H10 heart rate monitor, to later determine the aerobic capacity of each subject in ml/kg/min.
day 1 and 7 of the work shift
Glucose Curve (mg/dl)
Time Frame: from the beginning of the work shift up to 14 consecutive days
To determine the constant metabolic status of circulating glucose of the study subjects, a continuous glucose analyzer will be installed in each of them in the triceps area of the right arm, using the Abbott FreeStyle Libre analysis monitor. For which the triceps area will be cleaned with cotton and 75% alcohol to later install the measurement patch, which must remain for 14 continuous days, so it will be removed on day 14 (when each person returns to a new work shift). With this analysis, it is expected to know the behavior of plasma glucose in mg/dl.
from the beginning of the work shift up to 14 consecutive days
Body Composition (%fat mass, %free fat mass, %total body water)
Time Frame: day 1 and 7 of the work shift
Determination of body composition by percentage of fat mass, percentage of fat-free mass, percentage of total body water, (extracellular water, intracellular water and phase angle). To do this, the patient will be asked to remove all metal elements from the body along with as much clothing as possible. To carry out this entire evaluation, the InBody brand bioimpedance meter, model 270S, will be used.
day 1 and 7 of the work shift
Food surveys
Time Frame: day 2 of the work shift
Two dietary surveys will be carried out, the first is called "Evaluation of food consumption trends", while the second is a "24-hour intake count", with which macronutrients can be determined in grams.
day 2 of the work shift
Evaluation of movement intensity (METS/hora)
Time Frame: from day 1 of the work shift to day 14
The quantification of the movement of each of the subjects under study will be carried out through the use of an Actigraph accelerometer, model wgt3x-bt. Equipment that will be installed using an elastic belt on the right hip of each of the study subjects, which will determine the intensity of the movement, due to the intensity peaks that can be demonstrated in counts per minute, this information will give us the METs/hour of each of the study subjects.
from day 1 of the work shift to day 14
Heart Rate Quantification
Time Frame: from day 1 of the work shift to day 14
A POLAR heart rate monitor, model H10, will be used to maintain constant monitoring of each of the study subjects. This equipment will be installed on the chest of each individual, which must be in direct contact with the skin using an elastic belt, below the sternum, indicating pulses/minute.
from day 1 of the work shift to day 14
Muscle Strength (1RM)
Time Frame: Day 1 of the work shift and day 7 of the shift
Upper body strength evaluations will be carried out, through the use of hand dynamometers and another to determine back strength. Along with this, a calculation of one repetition maximum (1RM) will be carried out for the muscle groups: Pectorals, Quadriceps, biceps and hamstrings. Once these values are recorded, the study subjects from both groups will undergo an overload exercise program, in the same muscle groups mentioned above, using a format of 3 sets for 10 repetitions in each muscle group at 50% of 1RM, for 3 days of the work week, every 48 hours.
Day 1 of the work shift and day 7 of the shift

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Cardiac Variability
Time Frame: Day 1 of the work shift and day 7 of the shift
After taking initial exams and evaluations, an appointment will be coordinated with each of the study subjects during the first day of stay in conditions of hypobaric hypoxia at 2950 meters above sea level. At this time, the subject will be asked to lie on a stretcher, without moving and without speaking for 10 minutes, during which blood pressure will be measured every 2 minutes in the left arm, using an OMROM analyzer. Along with this, your heart rate will constantly be read using the Polar H10 heart rate monitor previously installed on your chest. heart rate that will be recorded by the KUBIOS HRV application, which will determine the heart variability of each of the subjects.
Day 1 of the work shift and day 7 of the shift

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Maintenance of baseline gut microbiota concentration during seven days under hypobaric hypoxic conditions.
Time Frame: From the start of the work shift until its end, for 7 consecutive days under hypobaric hypoxic conditions.
Due to the intervention of strenuous physical exercise and dietary supplementation, there should be no significant changes in the number of colony-forming units (CFU) of the intestinal microbiota of subjects working under hypobaric and hypoxic conditions, as determined by fecal DNA quantification.
From the start of the work shift until its end, for 7 consecutive days under hypobaric hypoxic conditions.
SF36 V2 Quality of Life Survey
Time Frame: The quality of life survey will be carried out on a single occasion, pre-intervention.
An individual survey will be conducted, using the SF36 Version 2 form, to determine the quality of life of each individual. This survey will be carried out digitally, pre-intervention, and to each of the subjects who enter the research project.
The quality of life survey will be carried out on a single occasion, pre-intervention.
determination of metabolic stress
Time Frame: Day 1 of the work shift and day 7 of the shift
5 ml of saliva will be requested in a polypropylene tube, which will be taken to the laboratory to determine the value of cortisol in saliva reached by each individual.
Day 1 of the work shift and day 7 of the shift
Pittsburgh Sleep Quality Survey
Time Frame: This sleep quality survey will be carried out once pre-intervention
This variable will be measured in all study subjects, for which the Pittsburgh survey will be used in digital format, and it will be carried out pre-intervention.
This sleep quality survey will be carried out once pre-intervention

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: jorge H Torres Mejías, Magister, Centro de Investigación Andino para la Altitud Geográfica

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

August 30, 2026

Study Completion (Estimated)

December 30, 2026

Study Registration Dates

First Submitted

April 21, 2026

First Submitted That Met QC Criteria

June 1, 2026

First Posted (Actual)

June 3, 2026

Study Record Updates

Last Update Posted (Actual)

June 3, 2026

Last Update Submitted That Met QC Criteria

June 1, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

Sharing the data of the patients with whom this research will be carried out will depend on whether the participant himself accepts, through informed consent, to share his studied background with the scientific community.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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