With your leg stretched out in front of you and the knee supported, make an imaginary line from the heelto the ground.
将你的腿前向伸展，膝盖绷紧，作一条从脚后跟到地面的垂线。
2
You may need orthotics to help your feet work normally during physical activity, especially if you are active and have knee pain or pain in the arch or heel area of your foot.