High Altitude HypoxiaNCT07063732
Ketone Monoester Supplements, High Altitude, and Brain Blood Flow During Exercise
A study testing Ketone Monoester (KME) in people with High Altitude Hypoxia and Exercise, run by McMaster University at 2 sites in 2 countries.
Trial summary
The purpose of this trial is to investigate the effect of acute ketone monoester ingestion (0.6 g KME/kg body weight) on the occurrence of the ventilatory threshold and the subsequent response of blood velocity in cerebral arteries during a maximal exercise test at low altitude and high altitude. Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- High Altitude Hypoxia, Exercise
- What is being tested?
- Ketone Monoester (KME)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 14 participants
- Where
- 2 sitesin 2 countries
- Study dates
- 28 May 2025to 31 Aug 2025
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Must be a member of the research expedition team travelling to the Barcroft Research Station in White Mountain California
Who cannot join
- BMI > 30
- No prescribed medications (oral contraceptives excluded)
- History of smoking
- Currently following a ketogenic diet or consuming exogenous ketogenic supplements
- History of heart, lung, blood vessel, or kidney disease
- Currently pregnant
Trial locations and contacts
2 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
2 sites in 2 countries
United States1 site, 1 recruiting
- Recruiting
Barcroft Research Station
Bishop, California, 93514
Jeremy Walsh, PhD, 9055259140, walshj18@mcmaster.ca
Canada1 site, 1 recruiting
- Recruiting
University of Guelph
Guelph, Ontario, N1G 2W1
Jeremy Walsh, PhD, 9055259140, walshj18@mcmaster.ca
About this study
Official title: The Effect of Ketone Monoester Supplementation and High Altitude on Exercising Cerebral Blood Flow
The purpose of this trial is to investigate the effect of acute ketone monoester ingestion (0.6 g KME/kg body weight) on the occurrence of the ventilatory threshold and the subsequent response of blood velocity in cerebral arteries during a maximal exercise test at low altitude and high altitude.
- Conditions
- High Altitude Hypoxia, Exercise
- Being tested
- Ketone Monoester (KME), Placebo
- Medical subject headings
- Motor Activity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ketone Monoester (KME)Dietary supplement
0.6 g KME per kg body mass; [R]-3-hydroxybutyl [R]-3-hydroxybutyrate. (Delta G Ketone, TΔS, Oxford).
PlaceboDietary supplement
Inert, calorie-free placebo drink that is taste-matched to the ketone monoester supplement
| Study group | Role | What they receive |
|---|---|---|
| High Altitude (3800m; Barcroft Research Station) | Experimental | High altitude setting Receives: Dietary Supplement: Ketone Monoester (KME); Dietary Supplement: Placebo |
| Low Altitude (334m; University of Guelph) | Experimental | Low altitude setting Receives: Dietary Supplement: Ketone Monoester (KME); Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cerebral Blood Velocity
Transcranial Doppler ultrasound will be used to measure blood velocity in the middle cerebral artery and posterior cerebral artery. Location of measurements will remain consistent within participants.
Measured: 3 hours
Secondary outcomes (8)
Cardiac Output
Cardiac output (L/min) will be measured using a non-invasive cardiac output monitor (Physioflow). The monitor uses signal morphology impedance cardiography to determine cardiac output.
Measured: 3 hours
Blood Pressure
Mean arterial pressure (mmHg) will be measured via a brachial cuff placed on the upper arm.
Measured: 3 hours
Ventilatory Threshold
Ventilatory threshold (VT) will be calculated based on previously described methods (Gaskill et al., 2001).
Measured: 3 hours
End-Tidal Gases
End-tidal oxygen (PETO2) (mmHg) and carbon dioxide (PETCO2) (mmHg) will be collected using a metabolic cart.
Measured: 3 hours
Rate of Oxygen Consumption and Carbon Dioxide Production
Rate of oxygen consumption (VO2) (mL/min) and carbon dioxide production (VCO2) (mL/min) will be collected using a metabolic cart.
Measured: 3 hours
Ventilation
Ventilation (Ve) (L/min) will be collected using a metabolic cart.
Measured: 3 hours
Blood Lactate and Beta-Hydroxybutyrate
Capillary blood will be obtained via finger prick using a lancing device to measure concentrations of blood lactate (mmol/L) and beta-hydroxybutyrate (mmol/L) using a handheld metabolite analyzer.
Measured: 3 hours
Peak Work Rate (Maximal Exercise Test)
The maximum wattage (W) achieved by the participant during the maximal exercise test will be recorded.
Measured: 3 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jul 2025
- Study start28 May 2025
- Primary completion31 Aug 2025 (estimated)
- Study completion31 Aug 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for High Altitude HypoxiaStudies of the same condition, open and under way.
- More trials run by McMaster UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Investigator, Outcomes assessor
- Enrolment
- 14 participants (estimated)
Sponsor and investigators
- Lead sponsor
- McMaster University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Jeremy Walsh, McMaster University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07063732
- Sponsor's protocol ID
- KETEX_WM
- Status last verified
- Jul 2025
- First submitted
- 28 May 2025
- Last updated
- 14 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Gaskill SE, Ruby BC, Walker AJ, Sanchez OA, Serfass RC, Leon AS. Validity and reliability of combining three methods to determine ventilatory threshold. Med Sci Sports Exerc. 2001 Nov;33(11):1841-8. doi: 10.1097/00005768-200111000-00007.
PubMed 11689733
Study at a glance
From the registry record, last updated by the sponsor on 14 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Ketone Monoester Supplementation and High Altitude on Exercising Cerebral Blood Flow
- ClinicalTrials.gov ID
- NCT07063732
- Acronym / sponsor ID
- KETEX_WM
- Conditions
- High Altitude Hypoxia, Exercise
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 14 participants (estimated)
- Lead sponsor
- McMaster UniversityUniversity, hospital or other
- Study start
- 28 May 2025 (actual)
- Primary completion
- 31 Aug 2025 (estimated)
- Study completion
- 31 Aug 2025 (estimated)
- First posted
- 14 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this trial is to investigate the effect of acute ketone monoester ingestion (0.6 g KME/kg body weight) on the occurrence of the ventilatory threshold and the subsequent response of blood velocity in cerebral arteries during a maximal exercise test at low altitude and high altitude.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| High Altitude (3800m; Barcroft Research Station) | Experimental | Dietary Supplement: Ketone Monoester (KME), Dietary Supplement: PlaceboHigh altitude setting |
| Low Altitude (334m; University of Guelph) | Experimental | Dietary Supplement: Ketone Monoester (KME), Dietary Supplement: PlaceboLow altitude setting |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (1 listed)
- Must be a member of the research expedition team travelling to the Barcroft Research Station in White Mountain California
Key exclusion criteria (6 listed)
- BMI > 30
- No prescribed medications (oral contraceptives excluded)
- History of smoking
- Currently following a ketogenic diet or consuming exogenous ketogenic supplements
- History of heart, lung, blood vessel, or kidney disease
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Ketone Monoester (KME)0.6 g KME per kg body mass; [R]-3-hydroxybutyl [R]-3-hydroxybutyrate. (Delta G Ketone, TΔS, Oxford). | Dietary supplement | High Altitude (3800m; Barcroft Research Station), Low Altitude (334m; University of Guelph) |
| PlaceboInert, calorie-free placebo drink that is taste-matched to the ketone monoester supplement | Dietary supplement | High Altitude (3800m; Barcroft Research Station), Low Altitude (334m; University of Guelph) |
Primary outcome
Cerebral Blood Velocity
Time frame: 3 hours
Transcranial Doppler ultrasound will be used to measure blood velocity in the middle cerebral artery and posterior cerebral artery. Location of measurements will remain consistent within participants.
8 secondary outcomes
Cardiac Output
Time frame: 3 hours
Blood Pressure
Time frame: 3 hours
Ventilatory Threshold
Time frame: 3 hours
End-Tidal Gases
Time frame: 3 hours
Rate of Oxygen Consumption and Carbon Dioxide Production
Time frame: 3 hours
Ventilation
Time frame: 3 hours
Blood Lactate and Beta-Hydroxybutyrate
Time frame: 3 hours
Peak Work Rate (Maximal Exercise Test)
Time frame: 3 hours
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Jul 2025.
- Background: PubMed 11689733Gaskill SE, Ruby BC, Walker AJ, Sanchez OA, Serfass RC, Leon AS. Validity and reliability of combining three methods to determine ventilatory threshold. Med Sci Sports Exerc. 2001 Nov;33(11):1841-8. doi: 10.1097/00005768-200111000-00007.
- Individual participant dataSharing planned: Undecided
Related trials for High Altitude Hypoxia
Not yet recruiting
Effect of High-flow Nasal Cannula Oxygenation on the Incidence of Hypoxemia During Painless Gastrointestinal Endoscopy in Patients at High Risk for Obstructive Sleep Apnea Syndrome in High-altitude Regions
Hypoxemia, Gastric Cancer (Diagnosis)
Not yet recruiting
Assessment of Total Pulmonary Resistance sPAP/CO Between High Altitude HA vs. Sea Level LA in Healthy Individuals H
High Altitude, Healthy Adult
Not yet recruiting
Assessment of Total Pulmonary Resistance sPAP/CO Between Sea Level LA vs. High Altitude HA After Re-ascent in Patients With Pulmonary Arterial Hypertension PAH
Pulmonary Arterial Hypertension (PAH), Pulmonary Vascular Disease
Not yet recruiting
Assessment of Total Pulmonary Resistance sPAP/CO Between Sea Level LA vs. High Altitude HA After Re-ascent in Healthy Individuals
High Altitude, Healthy
Not yet recruiting
Assessment of Six-minute Walking Distance 6MWD Between High Altitude HA vs. Sea Level LA in Patients With Pulmonary Arterial Hypertension PAH
Pulmonary Arterial Hypertension (PAH), Pulmonary Vascular Disease
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
2 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Ketone Monoester (KME) in people with High Altitude Hypoxia and Exercise, run by McMaster University at 2 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States, Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Cerebral Blood Velocity (time frame: 3 hours). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07063732, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Jul 2025.