Introduction
Optimizing human performance during stressful physical and cognitive conditions remains critical for high-stakes military operations. Tactical personnel often face intense environments that can induce cognitive fatigue, compromising decision-making and operational effectiveness. While caffeine is globally recognized as the most widely consumed psychoactive substance used to enhance alertness and cognitive function, its common side effects—such as anxiousness, micro-saccades (small, involuntary eye movements), and irritability—may negatively impact performance in tactical settings. Therefore, alternative or adjunctive interventions are necessary to mitigate these drawbacks while enhancing cognitive resilience.
Theacrine, a purine alkaloid structurally related to caffeine but with a notably longer half-life and lower potential for habituation and side effects, is proposed as a promising caffeine alternative or complement. This alkaloid potentially offers sustained cognitive benefits with fewer adverse effects, making it attractive for enhancing cognitive-behavioral performance under fatigue.