Part Three: Core
Start with three workouts per week, at five to ten minutes each (save time by doing them before or after strength sessions). For each workout, do two to three sets of the exercises below at six to eight reps each. After a month, you'll be strong enough to increase the reps to the 10–12 range. Add more sets as you become stronger. By the end of month three, you should be doing three sets of 10–12 reps five times per week. Each session should take 10–20 minutes.

BALL CRUNCH (UPPER ABS): Performing crunches on an exercise ball requires balance, so it's a great workout for skiers. Lie on your back over the ball, with your spine following the ball's curve. Slowly sit up and don't allow the ball to roll under your hips.

CAPTAIN'S CHAIR (LOWER ABS): Grip the handholds on the captain's chair at your gym and stabilize your back against the chair back, legs hanging down. Lift your knees in toward your chest, then return to the starting position. Don't want to go to the gym? Do bicycles. Lie on your back, knees bent, hands clasped behind your neck. Alternately touch each elbow to your opposite knee as you bring the knee in.

CABLE WOODCHOP (OBLIQUES): At the gym, do this key core-building exercise with the cable machine. At home, use a dumbbell or elastic exercise tubing. Stand with your feet shoulder width apart, knees bent. Your right shoulder should be next to the pulley on the cable machine, or the tree or wall where you've attached the tubing. Grab the handle with both hands and rotate to the left and down. When your hands reach your left thigh, reverse the motion. Do all reps on one side, then switch sides.