This exercise is very important for good biomechanics and to treat pain in the knee, hip, foot and ankle. It targets your deep hip rotators with your hips extended like they are when you are standing, walking, running etc. Lying with your hips, pelvis and spine in contact with the floor gives you input as to where your body is in space so that you can isolate these muscles with perfect alignment. This will help your hip, knee, foot and ankle alignment when you are standing as these muscles help to control pronation "your foot, ankle and knee rolling in"!
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