Effect of Acute Ingestion of a Ketone Monoester on Psychomotor Vigilance During Acute Severe Hypoxia Exposure.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 42560222 · doi:10.1093/milmed/usag123
What was done
In a double-blind crossover trial, 16 male participants completed a psychomotor vigilance test while wearing a reduced oxygen breathing device during normoxia (15 minutes; 0 m; 20.9% O2) followed 30 minutes later by acute severe hypoxia (15 minutes; simulated altitude of 6,096 m, 9.7% O2). The protocol was conducted on two separate occasions following acute ingestion of either (R)-3-hydroxybutyl (R)-3-hydroxybutyrate ketone monoester (650 mg/kg body mass) or a taste-matched placebo.
What was found
Ketone monoester ingestion significantly increased blood R-βHB concentration (>3 mM; P < .001) and lowered blood glucose by ~20 mg/dL (P < .01) relative to placebo. Heart rate increased in hypoxia for both ketone monoester [13.6 (95% CI: 6.7, 20.7) bpm; P < .01] and placebo [13.2 (95% CI: 9.2, 17.2) bpm; P < .001], with no between-group difference in the magnitude of change (P = .87). The hypoxia-induced decline in mean reaction time was attenuated (P = .002) with ketone monoester, yielding a 25.5 (95% CI: 10.7, 40.3) millisecond faster mean reaction time compared to placebo. No significant differences were observed between conditions for other psychomotor vigilance test outcome measures.
Why it matters
Acute exogenous ketone monoester supplementation may help preserve psychomotor processing speed under acute, severe hypoxic stress.
Limits
The sample was small (n = 16) and restricted to males. Hypoxia exposure was acute and brief (15 minutes), and the beneficial effect was limited to mean reaction time without extending to other psychomotor vigilance parameters.
Cited by
- supports Administration of exogenous ketones without dietary changes improves cognitive retention during acute hypoxic exposure at altitudes between 15,000 and 20,000 feet.