http://www.antifragilemovement.com
There is an intimate relation between the horse stance and the side split. This in the sense that the weak link is mostly a lack of strength and hip opening in the extended ranges.
In this video I demonstrate the proper transitioning from a horse stance into the side split; The only way to go is DOWN. Don't come up if you straighten the legs!
A mistake is to treat the horse stance as a sumo squat which it is not.
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