At the center of all of my programs lies a fundamental focus on what I call "core development:" the building of strength and mobility into the TRUNK area of your body (abs, lower back and the many smaller, stabilizing muscles within). Solid core development is vital for teaching your body to move dynamically in skiing or any sport, and it is a huge factor in preventing injury and staying healthy during athletic endeavors.

By becoming stronger and more mobile in your trunk area, you take the strain off of your limbs, and your movements in general become more powerful and more efficient. When trying to tackle moguls or skiing in the trees, this type of strength is crucial!

I have highlighted below a few exercises I use with my athletes to develop their cores. Most of these exercises utilize the stability ball. And while they work the abs, they can also be used with the standard ab routine, done in conjunction with your regular workout or on their own. The exercises below are great for skiing but can also be applied to many other athletic activities.

The Skier Crunch

This exercise mimics the absorption motion of skiing on a horizontal plain. It uses the hip flexor muscles in your legs as well as your entire trunk for balance and stabilization. It is derived from a Paul Chek exercise called the "Jack Knife" and is an excellent way to get in the habit of initiating movement from your core.

• Start extended with your body straight, toes on the ball, hands straight below your chest.
• Maintaining perfect abdominal squeeze, roll the ball up under your hips, so you’re balancing on the top of your toes. Hold for two seconds and extend. Maintain that squeeze!
• Work up to two sets of 15 with perfect form, and then try it with only one leg.
• With advanced athletes, you can vary the pace and also vary the angle of the crunch to mimic the "angulation" motion used in initiating a turn in skiing.

The Back Scratcher

Besides mimicking certain aerial maneuvers of skiers and snowboarders, the Back Scratcher exercise builds strength into the hamstring and the backside of your body, while continuing to challenge the stabilizer muscles of your trunk. Paul Chek first pioneered this exercise as the "Supine Jack Knife," and it’s applications to the sporting world are vast. For those who ski a lot, this is a great way to maintain muscle balance between the quads and the hamstrings, and therefore an excellent tool for injury prevention!

• Start with heels on the ball, shoulders on the ground (spread arms for balance, if needed).
• Use your trunk muscles to straighten your body like a board.
• Maintaining pelvic stability, curl your legs while rolling the ball toward you until the toes of your shoes are pressed against it.
• Hold for two seconds and straighten.
• Work toward two sets of 12 with perfect form, then try it with only one leg on the ball.

Back Extension with Twist

The lower back is a major body tool in skiing, especially in uneven terrain and moguls. By building in a twist in the motion of the back extension, we get the body used to moving on multiple plains, so that the muscles will respond when we make a quick turn or go over a mogul while turning.

• Position the ball in front of a tree or bench for leverage, and with slightly bent legs, bend your body over the ball.
• Focusing on the abs and lower back muscles, extend your body up to a straight position (approximately 45 degrees up from the ground), and at the peak of the extension, perform a slow controlled twist to one side. Breathe OUT as you twist, releasing the spine’s range of motion. Lower to the count of two, then extend up and twist to the other side.
• Work up to two sets of six each side (12 total per set) and then try doing two sets of 12, with controlled twists to each side on each repetition.

Aerobesic with Twist

The Aerobesic is used to challenge your balance and to build stabilizer muscle recruitment into your twisting motion. This exercise adds power to any twisting action you may do while skiing, and generating balance and movement from your core greatly decreases your chance of injury during a fall. I learned this exercise at the VIS and have applied in various ways to all of my athletes' programs.

• First, establish a good aerobesic position, with your planted leg slightly bent and your body parallel to the ground (it is ok to have a slight bend in the back leg).
• Maintain a nice "wrap" sensation with your abs and lower back and pull shoulder blades back slightly.
• Without "opening" your hips, rotate your upper body slowly as far as you can first to the left and then to the right (two seconds up, two seconds down), maintaining posture and a parallel body position to the ground. Breathe OUT as you rotate.
• Check and reset your position (no sagging) and repeat.
• Work up to two sets of six to each side and then try making the twisting motion fast/explosive or do it with your eyes closed. When you progress past that, try throwing a medicine ball to a partner as you twist.

For anyone looking to increase fitness for skiing or any other dynamic sport, building strength and mobility into the core center of your body is the absolute KEY! Good luck, and go big!