Exogenous KetosisEarly Phase 1NCT07224282
The Effects of Ketone Supplements With Carbohydrates on Cycling Performance Above Lactate Threshold
A Early Phase 1 study testing Ketone supplementation and Carbohydrate in people with Exogenous Ketosis, run by University of Oklahoma at 1 site in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 55 yearsHealthy volunteers can take part
- Conditions the study is for
- Exogenous Ketosis
- What is being tested?
- Ketone supplementation and Carbohydrate
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 15 participants
- Where
- 1 siteUnited States
- Study dates
- 17 Nov 2025to 3 May 2026
- Phase
- Early Phase 1
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 55 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- 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.
Who cannot join
- Cardiovascular disease
- Respiratory disease
- Gastrointestinal disease
- Metabolic disease
- Kidney disease
- Neurological disease
- Pregnancy
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
University of Oklahoma
Norman, Oklahoma, 73019
Rebecca Larson, Ph.D, 405-325-5211, rdlarson@ou.eduu
About this study
Official title: The Effects of R-1,3-Butanediol With Carbohydrate Supplementation on Cycling Performance Above Lactate Threshold
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?
Read more
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.
Read the detailed description
The significance of this study is to address gaps in the literature by investigating the combined effects of R-1,3-Butanediol and carbohydrate supplementation on cycling performance during steady-state exercise above the lactate threshold. Participants include:
- Trained cyclists ages 18-55
- ≥ 6 hours of cycle training per week.
- Above average VO2max for their age range per ACSM guidelines.
- The sample is drawn from the University of Oklahoma, local cycling events in Oklahoma, and local bicycle shops.
There will be a total of three visits, lasting approximately one hour and separated by at least 7 days. The protocol begins with a familiarization visit, during which participants complete a maximal graded exercise test. They are instructed to be at least 4 hours postabsorptive and not complete strenuous exercise within 24 hours of the initial visit, and each participant signs an informed consent form, fills out a POMS questionnaire, and exercise history questionnaire (PAR-Q). Participants' height and weight were recorded, and their bicycles will be connected to the cycling trainer or will use the Zwift One stationary bicycle. To determine VO2 max and lactate threshold, a continuous incremental cycling test will be performed. The test begins at 1 watt per kilogram of body weight and increases 0.5 watts per kilogram of body weight every 3 minutes until two of the following were reached: volitional fatigue, inability to maintain cadence within 10 rpm of their preferred cadence, maximal heart rate within 10 bpm of age-predicted max heart rate, or respiratory exchange ratio greater than 1.10 The intent is to provide insights into metabolic and performance responses beyond traditional exercise intensities. The findings could inform endurance athletes and coaches on nutritional strategies for sustaining performance during high-intensity efforts.The study aims to investigate the performance effects of a ketone supplement (R-1,3-Butanediol) with carbohydrate supplementation on cycling performance above the lactate threshold. It aims to determine whether time to fatigue will be affected and if blood lactate concentrations will decrease due to ketone supplementation. Hypotheses include:
Time to fatigue is increased with ketone supplementation and carbohydrates compared to carbohydrates alone.
Ketone supplementation with carbohydrates will produce lower blood lactate concentrations compared to carbohydrates alone.
- Conditions
- Exogenous Ketosis
- Being tested
- Ketone supplementation, Carbohydrate
- Keywords
- Exogenous ketones, Time to fatigue
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ketone supplementationDietary supplement
30-gram carbohydrate beverage with 5 grams of R-1,3-Butanediol every 30 minutes of experimental visit
CarbohydrateDietary supplement
Also called Dextrose
30-gram carbohydrate beverage with bitter flavoring
| Study group | Role | What they receive |
|---|---|---|
| Ketone supplementation with carbohydrates | Experimental | Not described Receives: Dietary Supplement: Ketone supplementation; Dietary Supplement: Carbohydrate |
| Carbohydrate supplement only | Placebo comparator | Not described Receives: Dietary Supplement: Carbohydrate |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to fatigue
Measured: Through study completion, an average of 2 weeks.
Secondary outcomes (3)
Blood lactate
Measured: Through study completion, an average of 2 weeks.
Blood Glucose
Measured: Through study completion, an average of 2 weeks.
Beta-hydroxybutyrate levels
Using a finger prick to obtain a drop of blood to measure beta-hydroxybutyrate levels in the blood.
Measured: Through study completion, an average of 2 weeks.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Nov 2025
- Study start17 Nov 2025 (estimated)
- Primary completion9 Mar 2026 (estimated)
- Study completion3 May 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for Exogenous KetosisStudies of the same condition, open and under way.
- 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
- Early Phase 1
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 15 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Oklahoma
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07224282
- Sponsor's protocol ID
- 18836
- Status last verified
- Nov 2025
- First submitted
- 28 Oct 2025
- Last updated
- 4 Nov 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
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.
PubMed 28116349Dearlove 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.
PubMed 32868580Leckey 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.
PubMed 29109686Shaw 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.
PubMed 30632425Cox 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.
PubMed 27475046