NCT07224282

Brief Summary

The goal of this clinical trial is to determine whether a ketone supplement with carbohydrates extends time to fatigue during cycling compared with a carbohydrate-only supplement in healthy, trained cyclists aged 18-55. The main questions it aims to answer are: Is the time to fatigue increased with ketone supplementation and carbohydrates compared to carbohydrates alone? Will ketone supplementation with carbohydrates produce lower blood lactate concentrations compared to carbohydrates alone? Participants will:

  • Perform a staged maximal cycling exercise test on a stationary bicycle.
  • Finger prick to obtain a drop of blood for lactate measurements.
  • Wear a mask connected to a metabolic cart to measure breath contents.
  • Perform a cycling exercise test to fatigue for at least one hour.
  • Consume either a ketone supplement with carbohydrates or a carbohydrate supplement during the exercise at least 4 times.
  • Finger prick to obtain a drop of blood to measure blood lactate, ketones, and glucose.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
15

participants targeted

Target at P25-P50 for early_phase_1

Timeline
Completed

Started Nov 2025

Shorter than P25 for early_phase_1

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

October 28, 2025

Completed
7 days until next milestone

First Posted

Study publicly available on registry

November 4, 2025

Completed
13 days until next milestone

Study Start

First participant enrolled

November 17, 2025

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 9, 2026

Completed
2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

May 3, 2026

Completed
Last Updated

November 4, 2025

Status Verified

November 1, 2025

Enrollment Period

4 months

First QC Date

October 28, 2025

Last Update Submit

November 3, 2025

Conditions

Keywords

Exogenous ketonesTime to fatigue

Outcome Measures

Primary Outcomes (1)

  • Time to fatigue

    Through study completion, an average of 2 weeks.

Secondary Outcomes (3)

  • Blood lactate

    Through study completion, an average of 2 weeks.

  • Blood Glucose

    Through study completion, an average of 2 weeks.

  • Beta-hydroxybutyrate levels

    Through study completion, an average of 2 weeks.

Study Arms (2)

Ketone supplementation with carbohydrates

EXPERIMENTAL
Dietary Supplement: Ketone supplementationDietary Supplement: Carbohydrate

Carbohydrate supplement only

PLACEBO COMPARATOR
Dietary Supplement: Carbohydrate

Interventions

Ketone supplementationDIETARY_SUPPLEMENT

30-gram carbohydrate beverage with 5 grams of R-1,3-Butanediol every 30 minutes of experimental visit

Ketone supplementation with carbohydrates
CarbohydrateDIETARY_SUPPLEMENT

30-gram carbohydrate beverage with bitter flavoring

Also known as: Dextrose
Carbohydrate supplement onlyKetone supplementation with carbohydrates

Eligibility Criteria

Age18 Years - 55 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Highly trained males and females
  • Ages 18-55
  • Greater than or equal to six hours of cycling training per week
  • Participants from the University of Oklahoma, Oklahoma cycling teams, and local cycling races in Oklahoma.

You may not qualify if:

  • Cardiovascular disease
  • Respiratory disease
  • Gastrointestinal disease
  • Metabolic disease
  • Kidney disease
  • Neurological disease
  • Pregnancy

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Oklahoma

Norman, Oklahoma, 73019, United States

Location

Related Publications (5)

  • Beltz NM, Gibson AL, Janot JM, Kravitz L, Mermier CM, Dalleck LC. Graded Exercise Testing Protocols for the Determination of VO2max: Historical Perspectives, Progress, and Future Considerations. J Sports Med (Hindawi Publ Corp). 2016;2016:3968393. doi: 10.1155/2016/3968393. Epub 2016 Dec 25.

    PMID: 28116349BACKGROUND
  • Dearlove DJ, Harrison OK, Hodson L, Jefferson A, Clarke K, Cox PJ. The Effect of Blood Ketone Concentration and Exercise Intensity on Exogenous Ketone Oxidation Rates in Athletes. Med Sci Sports Exerc. 2021 Mar 1;53(3):505-516. doi: 10.1249/MSS.0000000000002502.

    PMID: 32868580BACKGROUND
  • Leckey JJ, Ross ML, Quod M, Hawley JA, Burke LM. Ketone Diester Ingestion Impairs Time-Trial Performance in Professional Cyclists. Front Physiol. 2017 Oct 23;8:806. doi: 10.3389/fphys.2017.00806. eCollection 2017.

    PMID: 29109686BACKGROUND
  • Shaw DM, Merien F, Braakhuis A, Plews D, Laursen P, Dulson DK. The Effect of 1,3-Butanediol on Cycling Time-Trial Performance. Int J Sport Nutr Exerc Metab. 2019 Sep 1;29(5):466-473. doi: 10.1123/ijsnem.2018-0284.

    PMID: 30632425BACKGROUND
  • Cox PJ, Kirk T, Ashmore T, Willerton K, Evans R, Smith A, Murray AJ, Stubbs B, West J, McLure SW, King MT, Dodd MS, Holloway C, Neubauer S, Drawer S, Veech RL, Griffin JL, Clarke K. Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes. Cell Metab. 2016 Aug 9;24(2):256-68. doi: 10.1016/j.cmet.2016.07.010. Epub 2016 Jul 27.

    PMID: 27475046BACKGROUND

MeSH Terms

Interventions

CarbohydratesGlucose

Intervention Hierarchy (Ancestors)

HexosesMonosaccharidesSugars

Central Study Contacts

Rebecca Larson, Ph.D.

CONTACT

Study Design

Study Type
interventional
Phase
early phase 1
Allocation
RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

October 28, 2025

First Posted

November 4, 2025

Study Start

November 17, 2025

Primary Completion

March 9, 2026

Study Completion

May 3, 2026

Last Updated

November 4, 2025

Record last verified: 2025-11

Data Sharing

IPD Sharing
Will not share

Locations