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

NCT07624409 | Enrolling By Invitation Early Phase 1

• 1 other identifier: CIAAG09/2026UCM
• Study Type: interventional
• Target: 22
• Locations: 1 country
• Sites: 1

Brief Summary

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

Conditions

Changes in Blood Glucose Under Hypobaric Hypoxia Conditions; Changes in the Intestinal Microbiota Under Hypobaric Hypoxia Conditions; Changes in Body Composition Under Hypobaric Hypoxia Conditions; Determination of Physiological Stress in Hypobaric Hypoxia

Keywords

microbiota in hypobaric hypoxia; body composition in hypobaric Hypoxia; Physical condition under hypobaric hypoxia conditions

Outcome Measures

Primary Outcomes (7)

• Aerobic Fitness, (ml/kg/min oxygen utilization)

  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)

  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)

  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

  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)

  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

  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)

  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 Outcomes (1)

• Cardiac Variability

  Day 1 of the work shift and day 7 of the shift

Other Outcomes (4)

• Maintenance of baseline gut microbiota concentration during seven days under hypobaric hypoxic conditions.

  From the start of the work shift until its end, for 7 consecutive days under hypobaric hypoxic conditions.

• SF36 V2 Quality of Life Survey

  The quality of life survey will be carried out on a single occasion, pre-intervention.

• determination of metabolic stress

  Day 1 of the work shift and day 7 of the shift

Study Arms (2)

Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

ACTIVE COMPARATOR

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.

Other: Overload Exercise Protocol; Device: Bioimpedanciometry; Device: heart rate; Device: continuous glucose analysis; Biological: gut microbiota analysis; Device: Accelerometer; Other: Evaluation of sleep quality, using the Pittsburgh survey; Other: Quality of life survey SF36 v2.; Procedure: Cardiac Variability Determination; Procedure: VO2 max estimate; Other: Encuesta alimentaria

Group undergoing resistance training plus probiotic intake.

EXPERIMENTAL

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.

Dietary Supplement: Probiotic Nutritional Intervention; Other: Overload Exercise Protocol; Device: Bioimpedanciometry; Device: heart rate; Device: continuous glucose analysis; Biological: gut microbiota analysis; Device: Accelerometer; Other: Evaluation of sleep quality, using the Pittsburgh survey; Other: Quality of life survey SF36 v2.; Procedure: Cardiac Variability Determination; Procedure: VO2 max estimate; Other: Encuesta alimentaria

Interventions

Overload Exercise Protocol OTHER

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.

Also known as: physical exercise, overload exercise, exercises under hypobaric hypoxia conditions

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Probiotic Nutritional Intervention DIETARY_SUPPLEMENT

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).

Also known as: Gut Microbiota Under Hypobaric Hypoxia

Group undergoing resistance training plus probiotic intake.

Bioimpedanciometry DEVICE

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.

Also known as: Body Composition, fat mass, free fat mass, Bioimpedanciómetry

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

heart rate DEVICE

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.

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

continuous glucose analysis DEVICE

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.

Also known as: glicemias continua, monitor de glicemia continua

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

gut microbiota analysis BIOLOGICAL

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).

Also known as: Gut microbioma

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Accelerometer DEVICE

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).

Also known as: Accelerometry, energy expenditure, moviment intensity

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Evaluation of sleep quality, using the Pittsburgh survey OTHER

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.

Also known as: Cuestionario Pittsburg

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Quality of life survey SF36 v2. OTHER

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.

Also known as: Quality of life

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Cardiac Variability Determination PROCEDURE

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

Also known as: Variabilidad Cardiaca

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

VO2 max estimate PROCEDURE

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.

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Encuesta alimentaria OTHER

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.

Also known as: consumer trend survey, 24-hour recall survey

Group undergoing resistance training plus probiotic intake.; Overload Exercise Protocol on Inflammatory Parameters in Subjects Under Hypobaric Hypoxia

Eligibility Criteria

• Age: 20 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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.

You may not qualify if:

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

Sponsors & Collaborators

• Jorge Torres Mejías: lead

Study Sites (1)

Observatorio ALMA

San Pedro de Atacama, Antofagasta, 1410000, Chile

Location

Related Publications (19)

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MeSH Terms

Interventions

Exercise; Heart Rate; Accelerometry; Quality of Life

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Vital Signs; Physical Examination; Diagnostic Techniques and Procedures; Diagnosis; Hemodynamics; Cardiovascular Physiological Phenomena; Circulatory and Respiratory Physiological Phenomena; Investigative Techniques; Health Status; Demography; Epidemiologic Measurements; Public Health; Environment and Public Health

Study Officials

• jorge H Torres Mejías, Magister

  Centro de Investigación Andino para la Altitud Geográfica

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: The lead researcher only collects data from all the individuals studied, so he will not know the subjects of the study analyzed.
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: profesor

Model Details: Study of two independent groups of people in parallel with different types of interventions, who are in hypobaric hypoxia conditions at the same time.

Study Record Dates

• First Submitted: April 21, 2026
• First Posted: June 3, 2026
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): August 30, 2026
• Study Completion (Estimated): December 30, 2026
• Last Updated: June 3, 2026

Record last verified: 2026-06

Locations

CL (1)