小华从电视中看到一些举重大力士稳稳地将超过自己体重的杠铃举过头顶,打破记录时,不是拍手,就是叫好。不过,他的小脑袋总想不通,一个人怎么会举起这么重的杠铃?还是做医生的叔叔为他解开了这个谜。原来,在人体内有一个被称之为“千斤顶”的脊柱(又称脊梁骨),它象一根分节的弹簧,支撑着人体百分之六十的体重。可以作屈伸、侧弯等动作。人们在站立时,脊柱 Xiaohua saw some weightlifting television from television steady over his weight barbell overhead, to break the record, not clapping, is applauded. However, his small head always can not understand, how a person can lift such a heavy barbell, or a doctor’s uncle solved the mystery for him. Originally, in the human body there is a spine (also known as the spine) called “jack”, which is like a sectioned spring that supports 60% of the body weight. Can be flexion and extension, bending and other movements. People stand in the spine