Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12624000126516
Ethics application status
Approved
Date submitted
19/07/2023
Date registered
12/02/2024
Date last updated
12/02/2024
Date data sharing statement initially provided
12/02/2024
Type of registration
Retrospectively registered

Titles & IDs
Public title
The Impact of Normobaric Hypoxia-inducing High-Intensity Interval Training Program on the Expression Levels of Selected miRNAs and Running Economy in Endurance-trained Athletes
Scientific title
The Impact of Normobaric Hypoxia-inducing High-Intensity Interval Training Program on the Expression Levels of Selected miRNAs and Running Economy in Endurance-trained Athletes
Secondary ID [1] 310156 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Aerobic performance 330733 0
Impact of Normobaric Hypoxia on the Human Body 330734 0
Running economy 330735 0
Condition category
Condition code
Respiratory 327579 327579 0 0
Normal development and function of the respiratory system
Blood 327580 327580 0 0
Normal development and function of platelets and erythrocytes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The objective of this study is to assess the impact of a 6-week High-Intensity Interval Training (HIIT) program under normobaric hypoxic conditions on the expression levels of selected miRNAs and running economy in endurance athletes. The research will be conducted as an experimental study on male track and field athletes specializing in middle and long-distance events (n=32) in four stages.

In the first stage, which will last for two weeks, volunteers will be recruited for the experiment, and all participants will undergo somatic measurements using bioelectrical impedance analysis (BIA) to determine body composition. The second stage, which will commence immediately after somatic measurements, will be divided into four parts, during which aerobic performance measurements will be conducted in hypoxia (3000 m above sea level), normoxia, running economy tests, and eccentric contraction-dominant effort measurements. Blood samples will be collected before and after each exercise test for biochemical analyses, and all tests will be conducted with appropriate methodological 3-day intervals.

In the third stage of the study, athletes will be randomly assigned to four groups, each consisting of 8 individuals: control, experimental with temporary exposure to hypoxia without training, experimental LLTL, and experimental LLTH. Athletes allocated to the experimental LLTL group will incorporate a 6-week (3 times a week) normoxic HIIT training program into their training plan, while the experimental LLTH group will undergo a 6-week (3 times a week) hypoxic HIIT training program. The training program will be conducted in a hypoxic chamber (two training groups of 4 individuals each) located at the Physiological Basis of Adaptation Laboratory, Bronislaw Czech Academy of Physical Education in Krakow, under the supervision of specialized technical staff, a physician, and a personal trainer, and will commence 3 days after the last exercise test. Training intensity will be monitored using subjective scale for assessing the degree of fatigue during physical activity and tree heart rate zones. The training will be conducted in an AMRAP system, with a ratio of 40 seconds of work and 20 seconds of rest.

The final, fourth stage will be conducted similarly to the second stage and will also be divided into four parts, including the aforementioned exercise tests and blood sample collection for biochemical analyses. A 3-day rest period will be implemented between the endurance tests. Additionally, to evaluate the long-term effects of the implemented training program, venous blood samples will be collected 21 days after the exercise tests.

LLTH Group (live low-train high):
Participants will stay and sleep in normoxic conditions at an altitude of approximately 223 meters above sea level (Krakow, Poland). Training sessions for this group will take place in a normobaric hypoxic chamber at the Krakow Academy of Physical Education, simulating an altitude of 2000-3500 meters above sea level (FiO2, 14.4%), following the designated training protocol. The oxygen fraction in the chamber will be continuously monitored. During their stay in the simulated high-altitude environment, participants will monitor their blood oxygen saturation (SpO2) using a pulse oximeter.

LLTL Group (live low-train low):
Throughout the entire study period, participants in this group will stay, sleep, and perform training under normoxic conditions at an altitude of approximately 223 meters above sea level (Krakow, Poland).

Hypoxia Without Training Group:
Participants in this group will stay in a hypoxic chamber at the Krakow Academy of Physical Education, simulating an altitude of 2000-3500 meters above sea level (FiO2, 14.4%), for 50 minutes 3 times a week for 6 weeks. However, they will sleep under normoxic conditions at an altitude of approximately 223 meters above sea level (Krakow, Poland), following the designated protocol. During their stay in the simulated high-altitude environment, participants will monitor their blood oxygen saturation (SpO2) using a pulse oximeter. The oxygen fraction in the chamber will be continuously controlled.
Intervention code [1] 326554 0
Treatment: Other
Intervention code [2] 326555 0
Early detection / Screening
Comparator / control treatment
The control group will remain in normoxic conditions at an altitude of approximately 223 meters above sea level (Krakow, Poland) throughout the entire study period, including sleeping conditions, and will not participate in the training program.
Control group
Active

Outcomes
Primary outcome [1] 335414 0
Changes in morphological parameters, running economy, threshold and maximum values before and after applying the training program. Running economy, threshold and maximum values assessed by VO2peak tests.
Timepoint [1] 335414 0
6 weeks after completion of the training program.
Primary outcome [2] 336078 0
Expression Levels of Selected miRNAs assessed by blood test.
Timepoint [2] 336078 0
6 weeks after completion of the training program.
Secondary outcome [1] 431264 0
Nil
Timepoint [1] 431264 0
Nil

Eligibility
Key inclusion criteria
- Athletes specializing in middle and long-distance events
- Aged 18 years or older
- No contraindications to physical exercise
- Absence of diagnosed metabolic disorders
- Not currently undergoing pharmacotherapy
Minimum age
18 Years
Maximum age
38 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Tobacco smoking
- Alcohol and substance abuse
- Staying at altitudes above 2000m for more than 48 hours within the 6 months prior to the study
- History of high-altitude sickness in family medical history
- Active infections or inflammatory conditions in the body
- Bleeding disorders

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Factorial
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
In calculating the size of the study group, the test for measuring group size of the Statistica program was used. Once the results of the study are available, correlation analyses and multivariate ANOVA, among other things, are planned.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
11/09/2023
Date of last participant enrolment
Anticipated
11/09/2024
Actual
Date of last data collection
Anticipated
6/12/2024
Actual
Sample size
Target
32
Accrual to date
16
Final
Recruitment outside Australia
Country [1] 25654 0
Poland
State/province [1] 25654 0
Malopolska

Funding & Sponsors
Funding source category [1] 314317 0
University
Name [1] 314317 0
University School of Physical Education in Kraków
Country [1] 314317 0
Poland
Primary sponsor type
University
Name
University School of Physical Education in Kraków
Address
University School of Physical Education in Krakówal. Jana Pawla II 78, 31-571 Kraków , Kraków , Poland
Country
Poland
Secondary sponsor category [1] 316800 0
None
Name [1] 316800 0
Address [1] 316800 0
Country [1] 316800 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 313427 0
Bioethics Committee at the District Medical Chamber in Kraków
Ethics committee address [1] 313427 0
Bioethics Committee at the District Medical Chamber in Krakówul. Krupnicza 11a, 31-123 Kraków, Kraków, Poland
Ethics committee country [1] 313427 0
Poland
Date submitted for ethics approval [1] 313427 0
16/05/2023
Approval date [1] 313427 0
22/05/2023
Ethics approval number [1] 313427 0
123/KBL/OIL/2023

Summary
Brief summary
This study aims to assess the influence of a 6-week High-Intensity Interval Training (HIIT) program conducted in normobaric hypoxia on the expression levels of specific miRNAs and running economy in endurance athletes. The research will be conducted as an experimental study on track and field athletes specializing in middle and long-distance events (n=60) in four stages.
In the first stage, volunteers will be recruited for the experiment, and all participants will undergo somatic measurements, with body composition determined using the bioelectrical impedance analysis (BIA) method. The second stage will be divided into four parts, during which aerobic performance measurements will be conducted in hypoxia (3000 m above sea level), normoxia, running economy tests, and eccentric contraction-dominant effort measurements. Blood samples will be collected by a laboratory technician before and after each exercise test for biochemical analyses, and all tests will be conducted at appropriate time intervals.
In the third stage of the study, the athletes will be randomly assigned (randomization) to four groups: control, experimental with temporary exposure to hypoxia without training, experimental LLTL, and experimental LLTH. Athletes allocated to the experimental LLTL group will incorporate a 6-week (3 times a week) normoxic HIIT training program into their training plan, while the experimental LLTH group will include a 6-week (3 times a week) hypoxic HIIT training program. The training program will be conducted in a hypoxic chamber located at the Physiological Basis of Adaptation Laboratory, Bronislaw Czech Academy of Physical Education in Krakow, under the supervision of specialized technical staff, a physician, and a personal trainer.
The final fourth stage will be conducted similarly to the second stage and will also be divided into four parts, including the aforementioned exercise tests and blood sample collection for biochemical analyses. Additionally, to evaluate the long-term effects of the implemented training program, venous blood samples will also be collected 21 days after the exercise tests.
Based on current knowledge, the proposed study may indicate a new training method that enhances the effectiveness of endurance training.
Research Questions:
1.To what extent does the application of a HIIT training program in hypoxia influence the expression levels of selected microRNAs (miRs)?
2.To what extent does the application of a HIIT training program in hypoxia influence the running economy of endurance athletes?
3.To what extent does the application of a HIIT training program in hypoxia influence the degree of muscle damage?
4.To what extent does the application of a HIIT training program in hypoxia influence the aerobic capacity of track and field athletes?
Trial website
Trial related presentations / publications
Public notes
Research Hypotheses:

- The HIIT training program in normobaric hypoxia improves running economy and aerobic capacity in endurance athletes.
- MicroRNAs serve as significant indicators of athletes' training proficiency and muscle damage.

Contacts
Principal investigator
Name 128122 0
Miss Izabela Kaczorowska
Address 128122 0
University School of Physical Education in Krakówal. Jana Pawla II 78, 31-571 Kraków , Kraków , PolandInstitute of Biomedical SciencesDepartment of Physiology and Biochemistry
Country 128122 0
Poland
Phone 128122 0
+48 531 309 390
Fax 128122 0
Email 128122 0
izabela.kaczorowska@doctoral.awf.krakow.pl
Contact person for public queries
Name 128123 0
Miss Izabela Kaczorowska
Address 128123 0
University School of Physical Education in Krakówal. Jana Pawla II 78, 31-571 Kraków , Kraków , PolandInstitute of Biomedical SciencesDepartment of Physiology and Biochemistry
Country 128123 0
Poland
Phone 128123 0
+48 531 309 390
Fax 128123 0
Email 128123 0
izabela.kaczorowska@doctoral.awf.krakow.pl
Contact person for scientific queries
Name 128124 0
Miss Izabela Kaczorowska
Address 128124 0
University School of Physical Education in Krakówal. Jana Pawla II 78, 31-571 Kraków , Kraków , PolandInstitute of Biomedical SciencesDepartment of Physiology and Biochemistry
Country 128124 0
Poland
Phone 128124 0
+48 531 309 390
Fax 128124 0
Email 128124 0
izabela.kaczorowska@doctoral.awf.krakow.pl

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
The data is to be collected and processed with: anthropometric measurements forms, questionaries, and statisticaltools (Statistica etc.). Participant data will be anonymised.
When will data be available (start and end dates)?
The data will be visible after the disclosure of the research process after June 12, 2024.
Data will be deposited after the project completion with the UPE Repository for an unlimited time. The data will be under embargo for 3 years until the investigators complete their analyses. The data generated by this project will not pose a disclosure risk. All data will be de-identified before depositing to the repository.
Available to whom?
The investigators of the project and their institution will hold the intellectual property rights for the research data they generate but will grant redistribution rights to a repository for purposes of data sharing. All potential participants will be given the study participant information sheet. Full written informed consent to the processing of the personal data will be provided by the signing, dating the paper consent forms (signed by parents/legal guardians of the underage participants and participants themselves, if they are of age).
Available for what types of analyses?
The data will be deposited with the AWF Kraków Repository as part of their permanent collection. The data deposited with the repository are retained at the servers and managed by the Repository team and backed-up regularly. Data in the repository will be provided: to achieve the aims in the study protocol and purpose research;
How or where can data be obtained?
DOI will be assigned to the dataset by the administrator of the AWF Repository when the data will be retained. The research data, as well as metadata, will be shared with the research community through the UPE Repository in the open formats (e.g. .xml).
http://repozytorium.awf.krakow.pl/xmlui/?locale-attribute=pl


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.