• Autonomic cardiovascular regulation adapts to microgravity and simulated unloading, revealing early arterial baroreflex adjustment, altered heart rate–blood pressure coupling, and differential sympathetic activity patterns across short- and long-duration exposure [1], [3], [9].

• Spaceflight- and bed-rest–induced cerebrovascular changes affect autoregulation and orthostatic intolerance, reflecting fluid shifts, vascular stiffness, and brain perfusion regulation challenges during and after exposure [12], [2].

• Bone and muscle integrity erode under unloading and radiation, with osteoblast differentiation suppression, muscle fibre atrophy, oxidative stress, and potential mitigations such as antioxidant strategies explored in simulated microgravity and animal models [6], [5], [4], [14], [13].

• Radiation exposure yields persistent cytogenetic damage and measurable biodosimetry signals in astronauts and aviators, underscoring long-term health risks and the need for biodosimetric monitoring [7], [15], [20].

• System-level approaches to space health include space medicine policy development, ISS medical operations management, life-support system analyses, and infrastructure for astrobiology experiments, highlighting integrated policy–technology pathways for crew health and mission sustainability [8], [11], [18], [10].