Research summary · Recovery and rehabilitation
Ketone ester intake altered REM sleep during a progressive training block
Twenty-four trained men followed seven weeks of progressively increased training while receiving ketone ester or a control drink after sessions and before sleep. Polysomnography and stress-recovery questionnaires were collected at baseline, week three and the programme's end.
- Publication year
- 2026
- First published online
- Publication type
- Double-blind controlled training study
- Journal
- Medicine & Science in Sports & Exercise
- Population / context
- Trained male athletes · Sleep and recovery
What the publication reports
REM sleep decreased in controls but increased in the ketone group by the final assessment, with a significant between-group difference. Early sleep-efficiency improvements occurred in both groups. Perceived sleep quality did not differ between groups, and perceived stress-recovery balance worsened in both.
Limits and interpretation
The small, male-only study examines sleep stages rather than proving improved competitive performance or long-term health. The abstract does not specify randomization. An objective REM difference is not equivalent to a perceived sleep benefit or a recommendation for routine supplementation.
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Consult the original record for the full author list, methods, references, funding and competing-interest disclosures.
An Intensified Training Period Reduces REM Sleep but this Decline Can Be Mitigated by Ketone Ester Supplementation
Original publication / indexed recordPMID: 42841497DOI: 10.1249/MSS.0000000000004172Reader discussion
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