My personal experience is to spread a carpet on the floor (to prevent the sound of sports from affecting the neighbors downstairs) and then run on it in situ. Attention, be sure to wear sports shoes to prevent spraining your ankle. The key point is that when you run, your arms are crossed behind your back, your head is raised and your chest is held high, and the time is controlled for more than one hour to achieve the ideal effect. It can not only reduce the fat on the back, but also treat cervical spondylosis caused by sitting in front of the computer for a long time.