A trial underlying a University of Birmingham personalized carbohydrate test reported individual carbohydrate doses of 49 to 80 g per hour, averaging about 65 g per hour, matching the oxidation achieved by a generic 90 g per hour protocol with 28 percent less carbohydrate, alongside lower perceived effort and less stomach fullness. These figures are as reported on the university's promotional page and should be verified against the published paper before citing.
The underlying trial is Podlogar, Cooper-Smith, Gonzalez and Wallis, Performance Nutrition 1:2, DOI 10.1186/s44410-025-00003-9, published April 9, 2025. The university page promoting it sits on a 2026 URL with no visible date.
The numbers
| Individual carbohydrate doses, as reported | 49 to 80 g/hr, averaging about 65 g/hr |
| Carbohydrate saved versus generic 90 g/hr at matched oxidation, as reported | 28% less |
What this does not show
- That this is new. The trial published April 9, 2025. The undated 2026 university page is promotion of an existing paper, not a new study.
- That anyone raced faster. The reported outcomes are matched oxidation, lower perceived effort and less stomach fullness, not performance in competition.
- That 90 g per hour is wrong for everyone. Individual doses ran as high as 80 g per hour. The range was wide, which is the point of personalization.
- That the numbers here are verified. The dose range, average and 28 percent figure come from the university's promotional page as reported; they were not checked against the published trial during the digest run.
Caveats worth holding
- Date trap: the trial published April 9, 2025, but the University of Birmingham promotional page sits on a 2026 URL with no visible date, inviting miscitation as new work.
- All figures are as reported by the university page and were not verified against the published paper during the digest run.
- Reported outcomes are oxidation, perceived effort and stomach fullness; competitive performance was not the reported result.
- Design details and participant numbers were not captured from the source.