Testosterone replacement for male military personnel: A potential countermeasure to reduce injury and improve performance under extreme conditions

Tactical operators, inclusive of soldiers in the military, are reliant upon their physiological and psychological state in often volatile and extreme life or death situations that require correct decisions and precise actions to ensure operational success with minimal collateral damage. Accordingly, the development of physical and mental resilience are hallmarks of prophylactic and remedial programs designed to ensure military personnel are combat ready, thus optimising their capacity to perform at expert levels, while reducing their risk of injury or the severity of injury sustained. Unfortunately, despite best efforts, current practices have not overcome the significant logistical challenges confronting a military service member's routine exposure to moderate and severe energy deficits upon deployment, resulting from unyielding energy demands and restricted energy intake during missions [1]. Consequently, these episodes of semi-starvation under complex and extreme tactical environments produces a cascade of interlinked negative outcomes, including a hypogonadal endocrine state (suppressed testosterone production), loss of muscle-bone mass and strength, reduced functional capacity, compromised cognition, and a suppressed immune system, culminating in greater susceptibility to injury, illness and sub-optimal performance, jeopardising their own welfare and the welfare of their comrades.