A supplement tested during a stage race
The study followed 18 trained mountain bikers taking part in the Absa Cape Epic 2025. Participants received either R-1,3-butanediol, known as BDO and marketed in this study under the brand Ketone IQ, or a placebo. Doses were taken after each stage and before sleep.
The researchers tracked heart rate, dietary intake, sleep measures, cognitive performance, and perceived stress and recovery. The aim was to evaluate this ketone precursor during prolonged competition rather than in a laboratory setting.
Mild ketosis, with no detected benefit
BDO did change the targeted biological marker: from the first stage, post-exercise beta-hydroxybutyrate concentration reached approximately 1.0 mmol/L. However, this increase was not accompanied by any detected benefit in the outcomes tracked compared with placebo.
Over the course of the race, both groups showed a decrease in exercise heart rate, an increase in resting heart rate, and increased energy and carbohydrate intake. Reaction time was also slower at the sixth stage. The authors interpret these findings collectively as a sign of accumulating physiological strain. BDO did not alter these trends.
A finding specific to this formulation
The abstract distinguishes BDO from ketone monoesters, citing research suggesting potential recovery benefits for the latter. These formulations are not interchangeable: a result obtained with one is not enough to establish the effectiveness of the other.
This trial therefore does not support the promise of better recovery with BDO under the conditions studied. It does not, however, demonstrate that all exogenous ketosis strategies are ineffective. With 18 participants and no detailed effect estimates in the abstract, the precision of the result remains difficult to assess.
Limitations to keep in mind
Only the Europe PMC abstract was reviewed, not the full text. The sample was limited to 18 trained mountain bikers during an eight-day race. The abstract does not provide numerical differences between groups or their uncertainty intervals. Adverse effects, funding, and conflicts of interest could not be verified.
What we can take away
BDO increased blood ketones but did not improve the markers tracked during this race. A measurable biological response is not, on its own, evidence of improved recovery.
Sources and provenance
- Post-Exercise R-1,3-Butanediol did not Improve Markers of Fatigue or Recovery During a Multi-Stage Mountain Bike Race.
Source date: 2026-11-01.
Randomized Controlled Trial, Journal Article · Résumé Europe PMC uniquement, texte intégral non consulté