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Beginning/Intermediate (gram on the left/mom in middle) – Using no weight and starting on all fours, kick one bent leg out to the side, squeezing your glute at the top of every rep. Try not to arch your back.
Advanced (me on the right) – Using a dumbbell or resistance band and starting on all fours, kick one bent leg out to the side, squeezing your glute at the top of every rep. Try not to arch your back.