人们在久坐或久站不动之后,伸上一个大大的懒腰,往往能给人带来非常愉悦的体验。这种舒服的感觉究竟是从何而来?一般来说,伸懒腰的动作都是身体后倾、上臂上扬,同时身体很多肌肉还会产生收缩作用,如此一来,体内的大部分血液就都被“边疆”地区的组织血管挤回了心脏,这些从体内各部分一路奔波赶回来的血液又会被心脏这个强力水泵泵进肺循环。由于伸懒腰的时 When people are sedentary or stand still for a long time, they reach a big lazy waist, often giving a very pleasant experience. In general, stretching movements are leaning back, upper arm rise, while many muscles in the body will produce contraction, so that most of the body’s blood will have been Blood vessels in the “frontier” regions squeezed back into the heart, and the blood that came back and forth from all parts of the body was pumped into the pulmonary circulation by the heart’s powerful pump. When stretching