肺活量:20岁开始下降肺活量从20岁起开始缓慢下降,到了40岁,一些人就出现气喘吁吁的状况。部分原因是控制呼吸的肌肉和胸腔变得僵硬起来,使得肺的运转更困难,同时还意味着呼气之后一些空气会残留在肺里,导致气 Vital capacity: 20-year-old began to decline The lung capacity began to decline slowly from the age of 20, to 40 years old, some people appear panting. Part of the reason is that the muscles and chest that control breathing become stiff and make the lungs more difficult to operate, but also mean that some air will remain in the lungs after expiration,