8. Lying Half-Jack
Targets shoulders, abs, and butt
Lying on ground on right side, torso propped up on right elbow, extend left arm straight up and touch left toes to top of step (left leg is turned inward so that toes point down).
Lower left arm 45 degrees as you raise left leg 45 degrees (toes point down throughout).
Return to start.
Do 12 reps; switch sides and repeat.