Stand sideways to a cable machine or band with the height of the cable adjusted to elbow height with your arms by your side. Step out and stretch the cable, then form a circle out away from the attachment point. Keep your lower body and spine quiet, flexing your glutes in a mini squat. Keep your shoulder down, a neutral tall spine, and a circle about hip width. This can be done ultra slow to increase intensity.
Why it works
This is a great core and glute exercise, that has a great turnover to any sport keeping certain things quiet, while others are active.