And finally we got an introduction to the process of bone remodeling, which is carried out by crews of osteocytes, osteoblasts, and osteoclasts.

最后，我们得到了骨骼重塑过程的介绍，这是由骨细胞、成骨细胞和破骨细胞团队进行的。

Space crews generally need to exercise at least 15 hours a week to slow down the process of bone degradation, but even that can't fully stave loss of bone density.

宇航员通常需要每周至少锻炼 15 个小时来减缓骨骼退化的过程，但即使这样也不能完全避免骨密度的损失。