The Kettlebellsireland split squat with rotation is a great corrective exercise that we have been using for many years, from Kettlebellsireland to FFI.

The benefits for this movement are;

1. Correct hyper-pronating ankles. If you have medial foot arches that collapse inwards when you squat or lunge then this movement will help train your foot, ankle, knee and hip joints function in a correct manner. By adding rotation to the lead leg, it shifts your body weight to the outside border of your foot.
2. Strengthen the Tibilais anterior and posterior in movement. Both of these muscles located in the lower leg help control your feet, helping them hold a neutral position when moving. These muscle can become weak in certain people, leading to poor gait and foot positioning.
3. Strengthen the peroneals. These muscles also located in the lower leg are also responsible for control of the feet and ankles. They work in opposition to the Tibialis muscles, so both muscle groups act like a stirrup, wrapping around the foot to keep it in neutral during locomotion.
4. Strengthen the hip adductors and abductors. Doing split squats with rotations tram your knee caps to track your middle toes when you bend your knees. Some people tend to have hip adductors that over fire when squatting / lunging with the result that their knees collapse inwards. 
5. This movement will help strengthen your Quads, hamstrings, glutes, calfs, in fact it will train every muscle in your lower body.

Add this to your strength training a couple of times per week. 5 reps or less each leg, for 3-5 sets

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