变速跑是近年来提倡的一种锻炼身体的方法,跑步时快跑一会儿,再慢跑一会儿,冲跑几步,再慢跑一会儿,这种方法适宜青年人(15～30岁)。这种跑法的优点在于:能使有机体在多变的状态下完成练习,实际刺激的强度增大,缺氧加剧,从而使中枢神经系统、心血管系统、呼吸系统和肌肉系统都能 Variable speed running is a method of physical exercise advocated in recent years. When running, run for a while, then jog for a while, rushing a few steps and then jogging for a while, this method is suitable for young people (15 to 30 years old). The advantage of this running method is that the organism can be practiced in a changing state, the intensity of the actual stimulus increases, and the hypoxia increases so that the central nervous system, the cardiovascular system, the respiratory system and the muscular system can both