Push-ups can help you workout the arm and core muscles you use during Missionary-style positions. From push-up position, with your hands under your shoulders, move your feet slightly forward so your body makes a "V" shape. Bend your elbows and move toward the floor. Once your chin nears the floor, swoop your hips down and your torso up until your hips nearly touch the floor. Reverse the move to the beginning and repeat. Do as many as you can (with good form) in 30 seconds.