Comparing glucose-to-fructose ratios during long endurance exercise
PILOT TEST OF GLUCOSE-FRUCTOSE RATIOS ON EXOGENOUS CARBOHYDRATE OXIDATION RATES DURING EXERCISE
This pilot will test whether changing the glucose-to-fructose mix from 2:1 (1:0.5) to 1:1 increases how much of the sugar you drink is burned for energy during long exercise for adults who do regular endurance training.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 10 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | University of Bath Academic / other |
| Locations | 1 site (Bath, Bath) |
| Trial ID | NCT07360249 on ClinicalTrials.gov |
What this trial studies
The trial compares two oral carbohydrate mixtures—glucose:fructose 2:1 (1:0.5) versus 1:1—to measure exogenous carbohydrate oxidation during prolonged exercise sessions. Eligible adult participants who perform at least 5 hours per week of endurance training will complete up to three hours of continuous exercise while ingesting the test beverages. The primary objective is to estimate the effect size of changing the glucose-fructose ratio on oxidation rates to inform sample size and design for a future definitive study. The protocol excludes people on glucose- or lipid-lowering or weight-loss medications, those with major chronic diseases, pregnancy or lactation, and anyone with contraindications to prolonged exercise.
Who should consider this trial
Good fit: Adults aged 18 or older who do at least 5 hours per week of endurance training, can tolerate three hours of continuous exercise, and do not have major chronic diseases or contraindications to exercise.
Not a fit: People with cardiovascular, renal, or liver disease, type 2 diabetes, those taking glucose- or lipid-lowering or weight-loss medications, pregnant or lactating individuals, or anyone unable to perform prolonged exercise are unlikely to qualify or receive benefit.
Why it matters
Potential benefit: If successful, the results could guide better carbohydrate formulations to help endurance athletes use ingested carbs more effectively and potentially improve sustained performance.
How similar studies have performed: Previous sports-nutrition research shows mixed glucose–fructose feeds increase carbohydrate absorption and oxidation compared with glucose alone, but head-to-head comparisons of 2:1 versus 1:1 ratios are limited.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age: 18 years and above; * Performing endurance training for at least 5 hours per week * Capable of three hours of continuous exercise Exclusion Criteria: * Glucose or lipid lowering, or weight loss medication * Diagnosis of cardiovascular disease, renal failure, liver disease or type 2 diabetes * Contraindications to exercise * Pregnant or lactating
Where this trial is running
Bath, Bath
- University of Bath — Bath, Bath, United Kingdom (Recruiting)
Study contacts
- Study coordinator: Javier Gonzalez
- Email: j.t.gonzalez@bath.ac.uk
- Phone: +441225385518
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.