Human spaceflight has been fascinating man for centuries, representing the intangible need to explore the unknown, challenge new frontiers, advance technology, and push scientific boundaries further. A key area of importance is cardiovascular deconditioning, that is, the collection of hemodynamic changes—from blood volume shift and reduction to altered cardiac function—induced by sustained presence in microgravity. A thorough grasp of the 0G adjustment point per se is important from a physiological viewpoint and fundamental for astronauts’ safety and physical capability on long spaceflights. However, hemodynamic details of cardiovascular deconditioning are incomplete, inconsistent, and poorly measured to date; thus a computational approach can be quite valuable. We present a validated 1D–0D multiscale model to study the cardiovascular response to long-term 0G spaceflight in comparison to the 1G supine reference condition. Cardiac work, oxygen consumption, and contractility indexes, as well as central mean and pulse pressures were reduced, augmenting the cardiac deconditioning scenario. Exercise tolerance of a spaceflight traveler was found to be comparable to an untrained person with a sedentary lifestyle. At the capillary–venous level significant waveform alterations were observed which can modify the regular perfusion and average nutrient supply at the cellular level. The present study suggests special attention should be paid to future long spaceflights which demand prompt physical capacity at the time of restoration of partial gravity (e.g., Moon/Mars landing). Since spaceflight deconditioning has features similar to accelerated aging understanding deconditioning mechanisms in microgravity are also relevant to the understanding of aging physiology on the Earth.

几个世纪以来，载人航天一直让人类着迷，它代表了探索未知、挑战新领域、推进技术和进一步突破科学界限的无形需求。一个重要的关键领域是心血管失调，即由微重力持续存在引起的血流动力学变化的集合——从血容量变化和减少到心脏功能改变。从生理角度来看，彻底掌握0G调整点本身非常重要，也是宇航员在长途太空飞行中的安全和身体能力的基础。然而，迄今为止，心血管失调的血流动力学细节还不完整、不一致且测量不善。因此，计算方法可能非常有价值。我们提出了一个经过验证的 1D-0D 多尺度模型，用于研究与 1G 仰卧参考条件相比对长期 0G 太空飞行的心血管反应。心脏做功、耗氧量、收缩性指数以及中心平均压和脉压均降低，加剧了心脏功能失调的情况。研究发现，太空旅行者的运动耐力与未经训练、久坐生活方式的人相当。在毛细血管-静脉水平上观察到显着的波形变化，这可以改变细胞水平上的常规灌注和平均营养供应。目前的研究表明，应特别关注未来的长途太空飞行，这需要在恢复部分重力时（例如，月球/火星着陆）立即具备体力。由于太空飞行失调具有与加速衰老类似的特征，因此理解微重力下的失调机制也与理解地球上的衰老生理学相关。