Somehow, the idea that it’s admirable to have “buns of steel” has become entrenched in our culture. It’s true that these muscles need to be strong, but if there’s too much steel back there—in the form of short, tight muscles—you’re likely to face a multitude of difficulties.
In everyday life, those can include sciatic nerve problems, low-back pain, and even knee trouble. That’s because tight buttock muscles limit the range of motion of the hips, leaving the low back and knees to compensate. Tightness in the posterior hips can also pull the knee out of alignment, thereby contributing to knee tendonitis and even arthritis. In yoga, you’re likely to come up against frustrating flexibility challenges, particularly in forward bends and seated twists.
Most often, the buttock muscles get overly tight when you spend a lot of time sitting, especially with crossed legs or ankles. Activities like cycling and running can also contribute. Whatever the cause, the solution is to do stretches and yoga poses that lengthen these muscles and teach them to relax. If you can squeeze in some butt stretches a few times a week, not only will your low back and knees be happier, but you’ll be rewarded with greater ease in your practice.
So what are these mysterious, hard-gripping, pose-disrupting muscles? The buttock muscles can be divided into two layers: the more superficial one is the gluteus maximus, which, when well developed, forms the rounded shape of the buttocks. It originates on the sacrum at the base of the spine and nearby pelvis, and then runs diagonally down and across the buttocks to insert on the outer upper femur (thighbone). When it contracts, it extends the hip, which pulls the femur into line with the torso. For example, the gluteus maximus contracts when you stand up.
In yoga, the gluteus maximus helps perform a similar job in partnership with the hamstrings when you move from a standing forward bend to standing upright. The gluteus maximus is also a strong external rotator of the hip, which, when you’re standing, turns the knees outward. The second and deeper layer of buttock muscles is made up of the six deep rotators. The piriformis is the best known, but this group also includes the internal and external obturators, the superior and inferior gemelli, and the quadratus femoris. They originate on the sacrum and the ischial tuberosities (sitting bones), and then run diagonally in a fan shape across the deep buttocks to insert on the back of the upper femur on the greater trochanter.
Backfield in Motion
There is good reason to develop strong rotators. They are important for moving and positioning the hip joint in daily activities and in standing poses. The primary action of the deep rotators is external rotation, and, like all muscles that are deep and close to a joint, they help to stabilize that joint. However, the piriformis is probably best known as a troublemaker, as it contracts and even spasms in association with low-back pain and may press on the sciatic nerve. This pressure can cause painful leg symptoms, including the shooting pain, deep aching, or even hot or icy sensations commonly called sciatica.
The gluteus maximus and the deep hip rotators are also responsible for horizontal abduction. This is different from standard hip abduction, which is what you do when you stand with your back against a wall and lift your leg straight out to the side. To experience horizontal abduction, stand on your right leg with your left hip and knee flexed up to 90 degrees each, as they’d be if you were sitting in a chair. Open the left leg out to the side so the left knee points to the left. This is the action that you’d perform to align the left knee over the left foot in Virabhadrasana II (Warrior Pose II) and in Parsvakonasana (Side Angle Pose).
But when both layers of buttock muscles are short and tight, they will pull the hip into external rotation, horizontal abduction, and extension, which means that internal rotation, horizontal adduction, and flexion will be limited. And that, in a nutshell, is what causes problems in forward bends and twists. When you’re sitting on the floor, tight buttock muscles, often in partnership with tight hamstrings, tend to tilt the pelvis backward, causing a slumped spine and reversing the normal lumbar curve, which can contribute to low-back strain and even disk injuries. This tendency to tilt the pelvis backward affects all sitting poses, including twists, cross-legged poses, and forward bends. In all these floor poses, the struggle to sit up can be eased by sitting on one or more folded blankets until you’ve had time to stretch the buttocks and hamstrings.
Stretch on Out
So how exactly do you go about loosening these troublemakers? Seated twists such as Ardha Matsyendrasana (Half Lord of the Fishes Pose) and its variations can be excellent tools. To try it, sit with your left leg bent on the floor, either sitting on the foot in the traditional pose or, if that’s not possible for you, placing the left foot just to the outside of the right hip. Then cross the right leg over the left, with the sole of the right foot on the floor outside the left thigh. Sit tall (on folded blankets as needed) and rotate your spine to the right as you draw the right knee toward the left armpit. Wrap the left elbow around the right knee, or even hook it on the outside of the knee, and use that leverage to pull the left chest up and toward the knee. In this position, the right hip is flexed, relatively internally rotated, and drawn in toward the midline rather than horizontally abducting. This pose isolates the posterior hip muscles, and they have no choice but to lengthen and to stretch. Repeat on the other side, crossing the right leg with the left foot.
You can also practice a couple of variations lying on your back. When you work supine, it’s easier to stay in the pose without struggling to sit upright, so you can experience a long, deep, relaxing stretch. Start by lying on your back and draw the right knee up and across your body until you feel the stretch in the back of the right hip. Or, from the start position, bend your knees and cross your right knee over the left. Lift the left foot off the ground and hold the left knee with your right hand, pulling it toward your chest. To deepen the stretch, hold the right ankle with your left hand and pull gently until you stretch the back of the right hip. Repeat the stretch on the other side.
Proceed with Caution
Move gradually into every hip stretch, listening to your body, because you can strain adjacent joints if you move too aggressively. The hip is a strong joint, and when it has moved as far as it can, continued pushing can pull the next joints above (the low-back and sacroiliac joints) and the next ones below (the knee and ankle) into directions that aren’t beneficial. This can happen in any stretch, including classical poses like Padmasana (Lotus Pose). And uncomfortable pressure or pain in the front of the hip when you pull the thigh up and across your torso doesn’t indicate a productive stretch; it means there’s compression on the tendons, ligaments, and other soft tissues that cross the front of the hip. Put a rolled hand towel in your groin—between the femur and lower abdomen—to open up the space, or move on to a different variation.
Practice your hip stretches two to three times each week; be sure to stay for a minute or two to breathe and relax into each one. Not only will the buttock muscles let go and lengthen but you’ll also have a chance to release any tendencies to keep a hard grip on your life.
Julie Gudmestad is a physical therapist and Iyengar Yoga teacher in Portland, Oregon. She regrets that she cannot respond to requests for personal health advice.