The Effects of Acute Ketone Monoester Supplementation on Exercise Efficiency and the Influence of Dose and Intensity

Diet can alter blood ketone levels and this in turn may affect exercise capacity. This study will determine if the acute ingestion of a ketone supplement alters cycling exercise efficiency. Participants will perform three trials in a randomized order. Each trial will involve an incremental exercise protocol on a stationary cycle ergometer to volitional fatigue. Participants will ingest either a high or low dose of a ketone supplement or a taste-matched placebo drink prior to exercise. Blood samples will be obtained to assess selected metabolic responses. This study will provide information regarding the effect of ketone supplementation on exercise efficiency.

Study Overview

• Status: Completed
• Conditions: Exercise; Ketosis
• Intervention / Treatment: Dietary supplement: Ketone monoester; Other: Placebo

Detailed Description

This study will determine if the acute ingestion of a ketone supplement alters cycling exercise efficiency. Trained participants with cycling experience will be recruited. Participants will perform three trials in a randomized order. Each trial will involve a 3-minute warm-up followed by an incremental ramp test. The ramp will initially consist of three, 5-minute stages performed at relative workloads corresponding to 75%, 100%, and 125% of individual ventilatory threshold intensity. This will be followed by a further incremental ramp test to volitional fatigue. Participants will ingest either a high or low dose of a ketone supplement or a taste-matched placebo drink prior to exercise using a randomized, double-blind crossover design. Diet prior to exercise will be standardized between trials for a given participant. Blood samples will be obtained to assess selected metabolic responses. This study will provide information regarding the effect of ketone supplementation on exercise efficiency.

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Hamilton, Ontario, Canada, L8S4K1
      • McMaster University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Be habitually consuming ≥50 g/d of carbohydrate (i.e., not following a ketogenic diet).
• Be engaged in endurance-type exercise >3h/wk.
• Have an estimated VO2peak of ≥90% for age and sex as estimated by an online calculator found at www.worldfitnesslevel.org.

Exclusion Criteria:

• Experiencing a condition that might preclude safe participation in physical activity and exercise, as determined by answering "Yes" to any question on Page 1 of the Canadian Society for Exercise Physiology Get Active Questionnaire.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ketone higher dose; An acute bout of exercise performed after the ingestion of a commercial supplement intended to provide ~0.6 g of ketone monoester per kg body mass of the participant.	Dietary supplement: Ketone monoester; A commercial liquid ketone monoester supplement.
Experimental: Ketone lower dose; An acute bout of exercise performed after the ingestion of a commercial supplement intended to provide ~0.3 g of ketone monoester per kg body mass of the participant.	Dietary supplement: Ketone monoester; A commercial liquid ketone monoester supplement.
Placebo Comparator: Control; An acute bout of exercise performed after the ingestion of a taste-matched placebo supplement.	Other: Placebo; A liquid placebo that is taste-matched to the ketone monoester supplement.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Exercise efficiency	Power output expressed relative to pulmonary oxygen uptake to determine cycling economy in watt per litre of oxygen per minute	Continuous measurement made over each of three, 5-minute consecutive stages of an incremental cycle exercise test at relative workloads corresponding to 75%, 100%, and 125% of individual ventilatory threshold intensity

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate	Mean heart rate	Continuous measurement made over each of three, 5-minute consecutive stages of an incremental cycle exercise test at relative workloads corresponding to 75%, 100%, and 125% of individual ventilatory threshold intensity
Rating of perceived exertion	Rating of perceived exertion measured using a 6-20 scale	Measurement made at the end of each of three, 5-minute consecutive stages of an incremental cycle exercise test at relative workloads corresponding to 75%, 100%, and 125% of individual ventilatory threshold intensity
Ketone body content in venous blood	Mixed venous blood content of the ketone body beta-hydroxybutyrate	Measurement made immediately prior to exercise

Collaborators and Investigators

• Sponsor: McMaster University
• Investigators: Principal Investigator: Martin J Gibala, PhD, McMaster University

Study record dates

Study Major Dates

• Study Start (Actual): December 27, 2022
• Primary Completion (Actual): May 31, 2023
• Study Completion (Actual): June 30, 2023

Study Registration Dates

• First Submitted: November 17, 2022
• First Submitted That Met QC Criteria: December 17, 2022
• First Posted (Actual): December 27, 2022

Study Record Updates

• Last Update Posted (Actual): July 10, 2023
• Last Update Submitted That Met QC Criteria: July 7, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: Efficiency
• Additional Relevant MeSH Terms: Metabolic Diseases; Acid-Base Imbalance; Acidosis; Ketosis
• Other Study ID Numbers: 15110

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No