You'll probably never need to lunge forward, thighs burning, to desperately thrust a sword at a charging enemy. But the thigh and hip strength that ancient Indian warriors relied on is still useful in all sorts of everyday activities: climbing stairs, swooping to snag a wayward toddler, or bending your knees to lift a load of laundry without straining your back. Just as important, strong thighs and hips can help protect your knees from arthritis, injury, and chronic wear and tear.
Few poses beat Virabhadrasana II (Warrior Pose II) at strengthening your hips and thighs. As you might guess from the way your legs burn in a long Warrior II, the pose strongly works your quadriceps muscles, which make up the front of your thighs.
But Warrior II is not just about strength: It can also correct a common misalignment that can lead to many knee problems. To see if you have this misalignment, stand barelegged in front of a mirror. If your alignment is healthy, your kneecaps will point straight out over the midline of your feet. But you may find that your thighbone rotates inward in relation to your shinbone and that your kneecap points slightly inward, too. This position is bad news: It torques your knee, putting uneven pressure on the cartilage and straining the supporting ligaments and tendons every time you bend it.
Whenever you hear a yoga teacher say, "As you bend your knee, point your kneecap directly toward your middle toe," she's reminding you to stabilize your thighbone and knee in healthy alignment. But that's often easier said than done. Even if your alignment is fine when you're standing with straight legs, you may collapse your front knee inward when you come into Warrior II.
To correct this misalignment, you need to focus on two actions in Warrior II. The first is stretching your hip adductors. This large muscle group, which fills your inner thighs and pulls your knees toward each other, includes the pectineus, adductor brevis, adductor longus, adductor magnus, and gracilis. To get a good long passive stretch for these muscles, practice this pose lying on your back: Lie perpendicular to a wall, with your feet on the wall and your knees and hips each bent to 90 degrees, as though you were sitting on a chair that had tipped over backward. Then open your knees to the sides and move your feet farther apart so your shins remain perpendicular to the wall and parallel to the floor. Stay in this position for four or five breaths and allow your inner thighs to relax and stretch.
Next, still lying on your back, create the shape of Warrior II: Leaving your right foot where it is, straighten your left leg out to the side, turning your foot in slightly as you ground your sole on the wall. Place your left foot so that a line drawn between its arch and your right heel would be parallel to the floor. Stretch your arms out to the sides at shoulder height, and—voilà! —Warrior II. Stay for a minute or two, and then repeat to the other side.
Up Against the Wall
The other secret to proper alignment of the bent leg in Warrior II is engaging and strengthening the muscles that externally rotate your thigh. The main external rotators are the gluteus maximus and the six deep rotators that lie underneath it—the piriformis, obturator internus, obturator externus, gemellus superior, gemellus inferior, and quadratus femoris.
To get in touch with and build these muscles, stand with your back near the wall and your feet 4 to 41/2 feet apart. Turn your left foot in slightly and your right foot out 90 degrees, parallel to the wall, and set yourself up so your right hip is touching the wall. (Don't force your left hip to the wall, or you'll force your right knee out of alignment.) Watch your thigh and knee as you bend your right leg into Warrior II: Make sure your right thigh is parallel to the wall and your right knee points out over the center of your right foot. Next, place a tightly rolled yoga mat between the wall and your bent knee. Pressing your knee firmly into this prop, press through your left foot, keeping your left knee straight and your left thighbone pushing back toward the wall. You should feel your right hip rotators working deeply to hold your right knee and thighbone in proper alignment.
Now apply the lessons you learned at the wall to Warrior II in the middle of the room. Make your pose "all in one plane": Firm your right buttock and tuck it into your body; press both knees, but especially your right one, toward an imaginary wall at your back. Move in and out of the pose, taking care that your knee doesn't wobble inward as you make your transitions.
Once you start to open your hip adductors and strengthen your external hip rotators so you can align your thighs and knees safely in Warrior II, you can intensify the work on your quadriceps muscles. Filling the whole front of the thigh, the four quadriceps converge into a single tendon that attaches to the patella (kneecap) and then connects, via the patellar ligament, to the upper tibia (shinbone); three of the "quads" originate on the upper thighbone, while the fourth comes from the pelvis, above the hip socket.
As soon as you bend your leg, your quads have to contract, or gravity would pull you to the floor. To work your quads even harder in Warrior II, bring your front—leg thigh parallel to the floor—but don't let that knee collapse inward or the back-leg thigh and knee collapse forward.
Practice Makes Perfect
Warrior II gives you a perfect opportunity to practice good biomechanics over and over, consciously and slowly. Training the quads and hip muscles to support your knees in their optimal, nontwisted alignment while you're bending your legs in yoga means you'll be less likely to hurt or strain your knees. But you can also extend these lessons to your daily life. Look down at each knee as you walk up stairs. As you place your right foot on the next step and begin to shift weight onto it, make sure you keep your knee centered over your foot. Also check to see whether you're using good alignment when you go down stairs, pedal your bike, or half-squat to pick up a child.
As you practice good alignment in Warrior II, you can learn healthy movement patterns with your body, not just with your intellect—so you'll be more likely to use these patterns in everything you do. And since Warrior II builds stronger quads, you'll have more leg power for when you need to lift a heavy load at the grocery store or in your yard—and that will help prevent back injuries caused by poor body mechanics. All in all, Warrior II can set the stage for a healthier yoga practice and a more active life for decades to come.