Start lying on your left side with your weight on your elbow. Your legs are almost straight and your feet stacked with the right on top. To modify: bend the bottom knee to rest on the mat while extending the top leg out.
Lift your pelvis off the floor, coming into a side elbow plank. Really lift the bottom of your waist up. Pull your shoulder blade down your back so your shoulder stays away from your ear (this will work your lat, too).
Hold for three seconds. Lower your pelvis back to the floor slowly and with control to complete one rep.