It’s important because any stiffness—anything less than 4° of motion—can affect your knees, hips, and lower back, and even your shoulders. A lack of ankle mobility affects your ability to properly transfer energy when your foot strikes the ground. With back squatting (a stationary move), ankle mobility allows for a positive shin angle. If your ankles are tight, then you will lean too far forward and put your back at risk.
The stretch:
Dorsiflexion stretch: Stand in a split stance, with the toes of your front foot 4-6″ away from a wall. Place both of your hands on the wall, with your weight on the balls of your back foot. Bend your front knee forward until it touches the wall and you feel the stretch in your ankle. Repeat for six to eight reps on both sides.
