I was teaching an out-of-town workshop and was just about to start a class when one of the students approached me. Looking a bit worried, she described a nagging pain at one of her sitting bones. The spot was tender to sit on, she said, and decidedly painful in some asanas. "What's causing the pain?" she asked. "What can I do about it?"
Sadly, I hear this complaint with increasing frequency as I talk with yoga students from all over the country. The problem usually arises in experienced practitioners with very flexible hamstrings—often women, though not always. The pain lingers on and on, with little or no progress toward healing. If these students were to discontinue all the poses that elicit the pain, their practice would be significantly limited. Often, they don't seek medical attention, because it seems like a relatively minor problem; instead, they opt to self-treat by practicing lots of poses that stretch the sore area.
There are a number of conditions that can cause pain at the sitting bone, including some serious lower back and sacroiliac injuries. If the pain is intense—especially if it is associated with pain in the back or farther down the leg—the situation should be evaluated by a health care provider who can establish an appropriate treatment plan. However, chances are very good that strained, overstretched hamstring muscles are the culprit. And if they are, there's good news: By changing his or her yoga practice, the student can support the hamstrings' natural healing process.
The Sitting Bone's Connected to the...
The hamstrings are the large group of three muscles that fill the back of the thigh. Two of the muscles, the semitendinosus and the semimembranosus, are in the medial (inner) section of the thigh. The third, the biceps femoris, is in the lateral (outer) portion of the back of the thigh. All three muscles originate on the ischial tuberosity—the bony protuberance at the bottom of the pelvis that is commonly called the sitting bone—and the biceps femoris has an additional attachment on the back of the femur, or thighbone. The hamstrings insert below the knee on the two lower leg bones, the tibia and fibula.
Most people can feel the hamstrings with their own hands—the muscles are the closest ones to the skin of the back of the thigh—and can follow them all the way down to the knee. It's even easier to find the hamstring tendons behind and just above the knee. To do this, place your heel out in front of you while sitting on the floor or in a chair. Keeping your knee partially bent, dig your heel into the floor as if you were trying to pull the heel toward you. When you do this, the tendons will stand out and be easy to see and touch.
The hamstrings have two primary actions: knee flexion (bending the knee) and hip extension. When you're squatting, your hips are flexed; you bring them into extension when you stand upright, placing the thighbones in line with the torso. When you stand on your right leg in Virabhadrasana III (Warrior Pose III) and lift your left leg to hold it parallel to the floor, your left hamstrings are creating hip extension. When you lie on your stomach, bend your knees, and lift your feet so you can grab your ankles for Dhanurasana (Bow Pose), the hamstrings are creating knee flexion. (The hamstrings also assist in rotational actions at the hip and knee.) To stretch your hamstrings, you need to keep your knee straight and flex your hip (in other words, fold the front of the thigh and the abdomen toward each other). One of yoga's classic hamstring stretches is Uttanasana (Standing Forward Bend), in which the knees are straight, the torso hangs down, and the abdomen eventually rests on the front of the thighs.
Too Much of a Good Thing
Why do so many yoga students develop the nagging, frustrating pain that indicates strained hamstrings? Think about the poses that usually make up your yoga practice. On an average day, do you do lots of poses that stretch your hamstrings? Do you do many standing forward bends, like Uttanasana and Prasarita Padottanasana (Wide-Legged Standing Forward Bend), and many seated forward bends? Chances are, the answer is yes; most students include quite a few of these poses in each practice session. Several other standing poses also lengthen the hamstrings, including Trikonasana (Triangle Pose) and Parsvottanasana (Intense Side Stretch Pose). And let's not forget Adho Mukha Svanasana (Downward-Facing Dog Pose). If you practice Ashtanga Yoga, Power Yoga, or a similar flowing yoga style, you probably do dozens of Down Dogs every time you're on the mat. All of this stretching can cause the hamstrings to become very flexible and even overstretched in relation to the other leg and hip muscles.
The plot thickens if you don't do much to strengthen your hamstrings. These long, vulnerable muscles are then liable to develop microscopic tears if a big load is placed on them, whether by stretching or contracting; they simply don't have the structural integrity to handle the intense pull developed by a big stretch or the internal tension developed by a big contraction, and the tissue breaks down.
I've never seen a practitioner create a dramatic and debilitating rupture to the main body of a hamstring by doing yoga, although such injuries are common in sports activities that demand more explosive hamstring movements and sudden violent stretching, such as football, baseball, soccer, and weightlifting. Instead, the usual breakdown in yoga students seems to be microscopic tearing where the hamstrings attach to the ischial tuberosities. The body responds to those tears with pain and inflammation, which includes swelling, so of course it's uncomfortable to sit on the sitting bones. The muscle still functions, but it will probably be uncomfortable to stretch or contract it.
A Repair Manual
The first lesson many yoga students with injured hamstrings need to learn is that stretching isn't always appropriate for injured or painful body parts. When you tear soft tissue, including muscles, tendons, and ligaments, your body begins its repairs by stitching tiny fibers of connective tissue across the damaged area. If you stretch the injured tissue, the tiny fibers can be torn loose, disrupting the healing process and lengthening the time needed for complete repair. In fact, if you repeatedly disturb the healing process, the tissue may never heal completely and the injured area can become chronically painful and inflamed. In addition, if the area does eventually heal, the repeated tearing and healing can create heavy scar tissue, which tends to receive less blood flow and be less pliable than normal tissue, setting the stage for reinjury.
By now it should be clear why my first recommendation to students with strained hamstrings is to stop stretching them immediately. Poses that put a lot of leverage on the hamstrings, like seated and standing forward bends, should be completely avoided during the healing process. Some other poses that normally pull on the hamstrings can be modified so they can be included in your practice without reinjuring the hamstrings. In Trikonasana, for example, don't lower your torso to your maximum; instead, place your hand on a block or a chair, removing the temptation to push too deeply into the pose. A similar modification with two blocks can be used for Parsvottanasana.
In Supta Padangusthasana (Reclining Hand-to-Big-Toe Pose), don't hold on to your big toe; instead, use a belt to catch your foot, and don't pull on it forcefully. In Utthita Hasta Padangusthasana (Extended Hand-to-Big-Toe Pose), rest your foot on a low ledge or piece of furniture so you feel no stretch in the back of the leg. In both poses, focus on strengthening the legs and lengthening your spine rather than on stretching your hamstrings. The bottom line in these modifications: Never elicit hamstring pain in any pose.
Patience, Patience, Patience
Once you stop stretching and reinjuring your hamstrings, the real healing can begin. Unfortunately, the hamstrings are notoriously slow to heal. Give them several weeks of rest at the very least. The healing progress is usually so gradual that you won't notice a day-to-day improvement. It's more likely that after a few weeks, you'll look back and realize that the pain and stiffness have decreased.
When you are aware that your hamstrings have improved and are less sensitive to movement, it's a good idea to add some mild strengthening to your healing regimen. Put on a heavy shoe, a boot, or a one-pound ankle weight and lie on your stomach. Keeping your thigh on the floor, lift your foot about a foot off the floor; this causes the hamstrings to contract as they flex the knee. Don't do more than 10 repetitions per session for the first week or so, then gradually increase to three sets of 10. (Aim for three sessions each week.) One pound is a very light resistance; if even this small amount of weight causes discomfort, you're not ready yet to begin strengthening. Wait another week or two and then try again. Remember that patience must be your mantra; sometimes the hamstrings can take three to six months to heal completely.
Strengthening is important to recovery not only because it increases circulation, which promotes healing, but also because strong, healthy muscle tissue is much less likely to tear in the future. So whether you are recovering from hamstring problems or simply want to prevent them, it's very important in your asana sessions to regularly include poses that strengthen the hamstrings, like Virabhadrasana I (Warrior I) and Virabhadrasana II (Warrior II) and Setu Bandha Sarvangasana (Bridge Pose). (To make sure you're engaging your hamstrings in Bridge, draw the tops of your shins back toward your tailbone.) If you want to supplement your yoga with other activities, walking and running are good hamstring strengtheners and also have the benefit of pumping life-giving blood through the muscle tissues. (Cycling is fine too, but it will build your hamstrings significantly only if your feet are clipped to the pedals.)
In general, it's best to stretch your hamstrings only after they've been warmed up by a walk or a series of active poses in which you don't push the edges of your hamstring flexibility. Be sure to practice a wide variety of poses, and avoid making hamstring stretches the narrow focus of your yoga sessions. Finally, don't be too aggressive in your hamstring stretches. Feeling pain in these poses can be a signal that you're doing microscopic damage to the muscles. Learn to be patient and present with the sensation of stretch rather than pushing it so far that it becomes pain. Your hamstrings are too central to most yoga poses—and to the rest of your life—to risk injuring them.