Heating up. Heat up your arms and legs, waist and back and the important parts, your ankles and knees, which is easy to injure in exercise.

• 准备活动。将四肢、胸、背、腹、腰、踝等部位充分活动开，方法是做操或小步慢跑。由于跑步对膝关节压力较大，因此要加强脚腕和膝关节的热身。