In the setting of altitude-induced hypoxia, operator cognitive capacity degrades and can compromise both individual and team performance. This degradation is linked to falling brain energy (ATP) levels and an increased reliance on anaerobic energy production from glucose. Ketone bodies are the evolutionary alternative substrate to glucose for brain metabolic requirements; previous studies have shown that the presence of elevated ketone bodies (ketosis) maintains brain ATP levels and reduce cerebral anaerobic glycolysis during hypoxia. Ketosis can be achieved when fasting or following a ketogenic diet; however, these approaches are impractical for military operators in the field. Exogenous ketone ester supplementation allows for rapid (
