判断跑步的方式（脚外旋呈八字形，由外旋到内旋，或者两脚平直）判断你跑步方式最容易的方法就是看你的就运动鞋磨损的情况。
Figure out how you run ( outside of your foot , outside to inside , or straight down the middle ) . The easiestway to determine how you run is to look at an old pair of running shoes .
外八字