The side plank is a simple move, but it covers a lot of ground. The isometric exercise requires no extra equipment or special skill, but works many muscle groups in the upper body. For women, it may help to strengthen the classic "problem areas" for both pear and apple-shaped bodies.
The side plank has several variations, but the basic move starts by lying on your side with your feet and legs stacked one on top of the other and toes pointed forward. Place your lower forearm and elbow on the floor, perpendicular to the rest of the body, and lift your hips upward. Rest your top arm along the plane of your body, or bend your elbow and rest your hand on your top hip. Your body should be in a "plank" position from feet to shoulder, so that the body is in a straight line from ankle to shoulder. This isometric exercise should be held for anywhere from 10 to 60 seconds, depending on your level of strength.
Generally speaking, the exercise strengthens the butt, back and abdominals. More specifically, that means the obliques, as well as the three gluteus muscles, the hip adductors, the pectoralis muscles and the latissimus dorsi. To work both sides of the body, you'll need to switch sides so each arm gets its chance being the lower arm.
If you're looking to get more of an abdominal workout, you can do a variation on the plank that includes more motion. Start in the plank position as described previously with your upper hand on your hip, and then look toward the ceiling and extend that upper arm upward so it's perpendicular with the rest of your body. Hold for a second, and then twist your body slightly to lower that upper arm down and tuck it under the space between your chest and the floor. Look downward when your arm is in this position. Return your arm back to the starting position -- you've just completed one repetition. Repeat this motion 10 to 12 times on each side of the body.
If you're a woman with a pear-shaped body, try another variation that will work to strengthen and tone the hips and legs. Start in the side plank, and then lift your upper leg until it is at the height of your head. Hold this position for 10 to 60 seconds. You can also add more intensity in the shoulders and obliques by resting your lower hand on the floor, instead of resting the elbow, so the lower arm is in a straight position.
Nicole Vulcan has been a journalist since 1997, covering parenting and fitness for The Oregonian, careers for CareerAddict, and travel, gardening and fitness for Black Hills Woman and other publications. Vulcan holds a Bachelor of Arts in English and journalism from the University of Minnesota. She's also a lifelong athlete and is pursuing certification as a personal trainer.