The aim is to stabilise the trunk in kneeling and control gluteus medius/maximus into shortening and lengthening in a weight bearing position.
Start in kneeling, making sure your hips are over your knees and your shoulders are over your hands. Find spinal neutral. Tip your pelvis backwards and forwards and then stop half way in between. Flatten your spine between your shoulder blades and gently draw your shoulders away from your ears. Now lengthen your neck by gently tucking your chin in. Engage your pelvic floor and deep transverse abdominals.
Now imagine you have a tray of drinks on your back and you do not want to spill a drop. Slowly sway your weight back over your knees as if you are going to sit on your heels. Stop half way and slowly come back up to the start position, all the time keeping your spine in neutral. What you should feel is your bottom muscles working, lengthening as you lower and shortening as you return to the start. If you cannot feel this, then at the same time gently squeeze a cushion between your knees. The trick is to keep your back from bending at all.
Progression: To make this doubly challenging, engage your shoulder blades at the same time as you transfer your weight back. Your lower trapezius will have to lengthen to control and shorten to return. It is also a nice way to strengthen serratus anterior which is the muscle that keeps your shoulder blades flush with your chest wall.
