Skip to main content
OpenTrials
Completed

NCT Number: NCT05588427

Effect of Ketone Ester Supplementation on Hypoxic Tolerance

This WP specifically aims to elucidate the effects of IEK on hypoxic tolerance and the development and severity of AMS symptoms, blood and tissue oxygenation status, as well as sleep quality during an episode of acute exposure to severe hypoxia.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Ketosis Acid-Base Imbalance Acidosis Altitude Sickness Cognition Disorders Cognitive Dysfunction Hypoxia Mental Disorders Metabolic Diseases Neurocognitive Disorders Nutritional and Metabolic Diseases Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Tract Diseases Signs and Symptoms Signs and Symptoms, Respiratory

Age range

18 year–35 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

KU Leuven

Leuven, Vlaams-Brabant, 3000, Belgium

About this study

Acute altitude exposure impairs exercise tolerance and performance, decreases the rate of maximal oxygen uptake (V̇O2max), cognitive function and sleep quality, and often also induces symptoms of acute mountain sickness (AMS). Previous studies have clearly indicated that ketone bodies exert a neuroprotective effect under hypoxic-ischemic conditions as well as improve hypoxic tolerance in rodents. In support of these earlier observations, recent pilot experiments in young volunteers in our laboratory provide proof of concept that IEK can attenuate oxygen desaturation during exercise in hypoxia. Therefore, given that impaired exercise tolerance in hypoxia is primarily due to impaired oxidative energy production in active tissues (brain and muscle), we hypothesize that IEK can increase blood and tissue (muscle and brain) oxygenation status in hypoxia and thereby enhance global hypoxic tolerance, as well as improve exercise tolerance and endurance exercise performance.

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

  • Males or females between 18 and 35 years old
  • Body Mass Index (BMI) between 18 and 25
  • Physically fit and regularly involved in physical activity (2-5 exercise sessions of > 30min per week)
  • Good health status confirmed by a medical screening
  • Non smoking
  • Normal sleep pattern as assessed by the Pittsburgh Sleep Quality Index (PSQI, appendix 2)

Exclusion criteria

  • Any kind of injury/pathology that is a contra-indication for hypoxic exposure and/or to perform high-intensity exercise
  • Intake of any medication or nutritional supplement that is known to affect exercise, performance or sleep
  • Intake of analgesics, anti-inflammatory agents, or supplementary anti-oxidants, from 2 weeks prior to the start of the study.
  • Recent residence or training under hypoxia; more than 7 days exposure to altitude > 1500m during a period of 3 months preceding the study.
  • Night-shifts or travel across time zones in the month preceding the study
  • Blood donation within 3 months prior to the start of the study
  • Smoking
  • More than 3 alcoholic beverages per day
  • Involvement in elite athletic training at a semi-professional or professional level
  • Any other argument to believe that the subject is unlikely to successfully complete the full study protocol

Treatment and study plan

Ketone ester

Dietary Supplement

A total of 240g ketone ester supplementation will be provided in one of the 28h experimental sessions in order to establish intermittent exogenous ketosis. Sucralose (5% w/w) is added to the ketone ester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate

Placebo

Dietary Supplement

Water, 5% sucralose (w/w), octaacetate (1 mM)

Primary outcomes

  1. Change in incidence of acute mountain sickness symptoms

    Time frame: Hour 0 - Hour 4 - Hour 10 - Hour 24 - Hour 28

    Scored by Lake Louise Scoring system

  2. Change in oxygenation status of brain, blood, muscle

    Time frame: Hour 1 - Hour 4 - Hour 10 - Hour 24 - Hour 28

    Measured by NIRS, pulse oximetry, blood samples

  3. Change in cerebral blood flow

    Time frame: Hour 1 - Hour 4 - Hour 10 - Hour 24 - Hour 28

    Measured using duplex ultrasound

  4. Time in hypoxia

    Time frame: From start of hypoxic exposure until subjects are too sick to comply to (supplementation) protocol or until end of protocol, up to 29 hours

    Total time that subjects were able to comply to the experimental protocol and supplementation protocol

Secondary outcomes

  1. Sleep quality

    Time frame: Throughout the entire duration of the night, up to 9 hours after individual bedtime

    Measured using polysomnography

Sponsors and collaborators

Lead sponsor

KU Leuven

Other

Registry information

Important dates

Study start
2022
Primary completion
2022
Study completion
2022
First posted
Oct 20, 2022
Registry last updated
Sep 5, 2023

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.

Related clinical trials

Published trials that share one or more normalized conditions with this study.