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NCT Number: NCT05447416

Intermittent Hypoxic Training (IHT) Versus Hyperbaric Oxygen Therapy (HBOT) for Aerobic Performance

Comparing the effect of HBOT and IHT on aerobic performance of athletes.

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Key information

Age range

18 year–45 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

The Sagol Center for Hyperbaric Medicine and Research Shamir Medical Center (Assaf Harofeh)

Zrifin, Israel

Location status: Recruiting

Location contact

Shai Efrati, Prof

CONTACT

[email protected]

972-8-9779393

About this study

Enhanced physical performance is the goal of all professional and non-professional athletes. There are many intervention methods aim to enhance physical performance from 2 intervention related to change in the environment partial oxygen pressure have been demonstrated to have beneficial effect: IHT and HBOT.

This study offers one of the two interventions to athletes with a pre and post intervention objective evaluation of the physiological performance - Maximal exercise test for evaluating VO2MAX and ventilatory thresholds, time to exhaustion, 30 seconds Wingate test, agility test, muscle biopsy, blood tests, brain MRI, cognitive tests and exercise cognitive test.

After signing an informed consent form, eligible subjects will be randomized to one of the study groups at a ratio of 1:1. The IHT group will receive three hypoxic guided training sessions per week, according an individualized training protocol, 24 sessions in total.

The HBOT group will receive 40 daily hyperbaric sessions, five days per week. Each session will include 90 minutes exposure to 100% oxygen at 2ATA with a five-minute air break every 20 minutes. Three times per week, as the IHT group, the HBOT group will have a guided training session, according an individualized training protocol.

Both groups, IHT and HBOT, will have the same relative intensity guided training protocols for 8 weeks, to stimulate the same exercise load. The IHT group will train for 60 minutes, 3 times a week in a normobaric hypoxia environment, at O2 concentration of 15.2% that stimulates a 2500-2600m height. The HBOT group will train for 60 minutes after the HBOT sessions, 3 times per week, in a normobaric normoxic environment

Physical performance evaluations will be conducted on 3 different times post interventions - a day last intervention, 3 weeks after and 2 months after - in order to analyze the long term effect of each intervention.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Vo2max above 3500 ml or Vo2max/kg above 50 ml/kg
  • Age 18-45
  • Subjects are active aerobic athletes, training regularly more than 4 exercise sessions per week.
  • Subject willing and able to read, understand and sign an informed consent

Exclusion criteria

  • Inability to attend scheduled clinic visits and/or comply with the study protocol
  • Active malignancy
  • Active smokers
  • Previous treatment of HBOT for any reason prior to study enrollment.
  • Chest pathology incompatible with pressure changes
  • Major orthopedic injury at the past 3 months
  • Inner ear disease
  • Lung pathology
  • The inability to perform an awake brain MRI
  • Claustrophobia
  • Previous neurologic conditions (e.g., Epilepsy, Brain tumors or s/p neurosurgery etc.)
  • Comorbidities and medications that rule out the subject

Treatment and study plan

Hyperbaric Oxygen Therapy - HBOT

Device

Each session will include exposure of 90 minutes to 100% at 2 ATA, with 5 minutes air breaks every 20 minutes

Intermittent Hypoxic Training - IHT

Device

Each session lasts 60 minutes of 15.2% oxygen at 1.0 ATA. Subjects will be training according to individualized training protocol.

Primary outcomes

  1. Cardiopulmonary exercise test (CPET)

    Time frame: Baseline, 11 weeks

    CPET determines the gas exchange dynamics that is expected to change through the intervention

Secondary outcomes

  1. Cardiopulmonary exercise test (CPET)

    Time frame: 8 weeks, 16 weeks

    CPET determines the gas exchange dynamics that is expected to change through the intervention

  2. Time To Exhaustion

    Time frame: Baseline, 11 weeks, 16 weeks

    The test will be conducted on the SRM high performance ergometer on 105% of the maximal aerobic power

  3. Wingate 30 seconds anaerobic test

    Time frame: Baseline, 11 weeks, 16 weeks

    The Wingate Anaerobic Test (WAnT) is conducted on the SRM high performance ergometer.

  4. Muscle biopsy for mitochondrial function

    Time frame: Baseline, 11 weeks

    Participants will undergo a muscle biopsy, muscle sample will be analyzed using the Oxygraph (Oroboros Inc, Austria) for oxygen respiratory function, as well as staining for mitochondrial proteins

  5. Blood test for evaluation of CBC

    Time frame: Baseline, 11 weeks, 16 weeks

    complete blood count

  6. Blood test for evaluation of HIF-1α

    Time frame: Baseline, 7 weeks, 8 weeks, 11 weeks, 16 weeks

    Hypoxic inducible factor 1α levels

  7. Blood test for evaluation of Telomeres length

    Time frame: Baseline,11 weeks, 16 weeks

    Using staining and FACS technology telomere length will be analyzed

  8. Blood test for evaluation of mitochondrial function

    Time frame: Baseline,11 weeks

    Mitochondrial function of Peripheral Blood Mononuclear Cells (PBMC) and Platelets (PLT)

Other outcomes

  1. Cognitive Function

    Time frame: Baseline, 11 weeks

    Cognitive function will be evaluated using the Neurotrax computerized cognitive assessment and the Cambridge Neuropsychological Test Automated Battery (CANTAB).

  2. Cognitive Function under exercise

    Time frame: Baseline, 11 weeks

    Participants will be asked to pedal on a bike on workload correlated to 85% of the second ventilatory threshold obtained during the CPET and will simultaneously perform a Stroop test using the EncephalApp Stroop Test application on a tablet.

  3. Whole-brain quantitative perfusion imaging

    Time frame: Baseline, 11 weeks

    Whole-brain quantitative perfusion imaging will be performed using Dynamic susceptibility contrast (DSC)-MRI technique

  4. Brain microstructure MRI evaluation

    Time frame: Baseline, 11 weeks

    Fractional anisotropy (FA) and Mean diffusivity (MD) will be evaluated using diffusion tensor imaging (DTI) MRI protocol

  5. Brain functional connectivity imaging

    Time frame: Baseline, 11 weeks

    Resting state functional MRI

  6. Pulse Rate variability and activity

    Time frame: baseline to 16 weeks

    Participants will be asked to wear a smartwatch (Garmin, USA) in the entire time frame of the study.

Study contacts

Contact information is provided by the study sponsor or research team.

Shai Efrati, Prof

CONTACT

[email protected]

972-8-9779393

Sponsors and collaborators

Lead sponsor

Assaf-Harofeh Medical Center

Other Gov

Registry information

Official study title

Intermittent Hypoxic Training (IHT) Versus Hyperbaric Oxygen Therapy (HBOT) for Aerobic Performance - Prospective Randomized Study

Important dates

Study start
2023
Primary completion
2027
Study completion
2027
First posted
Jul 7, 2022
Registry last updated
Apr 21, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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