No one is saying either you or your partner need to do a full split. But the more hip and hamstring flexibility you have, the more you'll be able to experiment with new positions. Most men have limited flexibility in this area, so take it slow and start with a lunge stretch. Have one foot forward (knee bent) and the other leg behind you with your shin on the floor. Press your weight forward through your hips with your arms at your side (or hands rested on your knee) and your back straight. Hold for 20 to 30 seconds and switch sides.