If you are experiencing an achy back, your hips may be to blame.

Tight hips can cause discomfort or stiffness in the lower back, groin, hip or thigh, which is worse with stairs, squats or other activities that require active hip flexion, says Sal Frangiamore, M.D., an orthopedic surgeon for the Summa Health Orthopedic Institute and team physician for the US Ski and Snowboard Association (USSA).

Dr. Lev Kalika, owner of New York Dynamic Neuromuscular Rehabilitation & Physical Therapy in New York City, adds: “The low back is intimately connected to our hips. The lumbar spine sits on top of the pelvis, and the hips and pelvis cannot be separated functionally.” Because of this, Dr. Kalika explains that hip mobility prevents over recruitment of back muscles.

As a yoga instructor, I have a few favorite stretches for the hips — and they’re not just my favorites because they feel good; they’re extremely functional and work the hip from all angles. Frangiamore is also a fan of these yoga poses. “Stretches like the pigeon pose, warrior 1 and groin stretches all work to lengthen muscles that attach around the hip joint (the pelvis and thigh bone), which become shortened after prolonged sitting or resting,” he says. “Lengthening these muscles can decrease tension and excessive pull on the hips and lower back which can improve posture and decrease associated pain.”

Ready to get loose? Give these three stretches (and modifications) a try.

Stretch #1: Pigeon

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Pigeon pose is excellent for stretching the glutes — and loosening up the glutes will help to loosen up the hips. Kalika says pigeon pose stretches deep hip rotators, which are muscles that "control hip stability because they are next to the joint and some of them connect to the joint capsule," he explains. "When bigger glute muscle movers (like the gluteus maximus and the superficial portion of medius) get weak, the deeper hip rotators get tight. This causes a vicious circle where weakness promotes tightness and tightness disallows strength gains.”

How to: For Pigeon, start in downward facing dog and then step your right leg forward. Align your right shin so that it’s parallel to the front of the mat (or as parallel as you can make it), and lower down onto your left knee. Then, lower the leg fully down on the ground and stay upright or fold forward over the right leg. Hold for 30 seconds while deeply breathing in through your nose and then out through your nose. Then, slowly wiggle out of the pose, go back to downward facing dog, and repeat with the left side.

If Pigeon is too intense for your body, Figure Four is a great modification. You can do the figure four stretch standing, sitting or lying down. Pick whatever is most comfortable to you. With the right ankle crossed over the left thigh, flex your right foot. Gently press the right thigh away from you (be careful not to press on the knee joint as it’s unsafe for the knee.) When you’re sitting or standing, you can gently lean further forward to go a little bit deeper. When you’re lying down, you can pull the legs in closer to your body to make the stretch more intense.

How to: For Figure Four, lie on your back with your knees bent and feet flat on the floor. Cross your right ankle over your left upper thigh. Thread your hands through your legs so that you can hold on to the back of your left leg. Gently pull the leg towards you, and flex the right foot. Hold for 30 seconds, breathing in through the nose and out through the nose, and then release and switch sides.

Stretch #2: Warrior I

Warrior I is a standing pose in yoga that helps loosen the front of the hips and works on spinal stability. The hip flexors are in the front of the hips and for many of us are shortened due to a sedentary lifestyle. In addition, Kalika says that the pelvis helps create a foundation for the spine, allowing the vertebrae to sit upright on top of each other. So the better your hip mobility, the better your spine and pelvis alignment will be. Warrior 1 requires the muscles to both lengthen and contract (Kalika says to think about how an umbrella opening looks); the movement helps lengthen the spine and ensures that the pelvis is positioned properly, which reduces back pain.

How to: To stretch the hip flexors, stand up in Warrior I with your feet as wide as your hips and your right foot forward a few feet. Bend the right knee so that it tracks over the right ankle, and then turn your left foot out to the left a little bit so that it’s on a 30 degree angle. Press down firmly through the outer edge of the left foot, and pull your abdominals in. Reach the arms up overhead, and feel a stretch in the front of the right hip.

Alternatively, you can get the same benefit by doing this in a lunge position. The only difference between Warrior I and a lunge is that in the lunge, your left foot will be off the floor and only the toes will be on the floor. Reach through your left heel and press down through the toes.

You can also do a low lunge and start this pose from your knees. Step your right foot forward and move your left knee back. Keep the feet as wide as the hips. Walk the hands to the inside of the right knee, and hold here or lower down onto your forearms for a deeper hip flexor stretch.

Stretch #3: Inner Thigh Stretch

Stretching the groin and inner thighs, muscles which are connected to the pelvis, can help tremendously with hip mobility and reducing back pain. This stretch releases the adductors (the upper thigh muscles that pull the legs together), which are often called upon when glutes, core and/or hip muscles are weak. This can leave them tight and shortened, which prevents hip movement, explains Kalika.

How to: Sitting down on the floor, open your legs wide apart. Flex your feet and engage your quads. If you cannot sit upright in this position, sit on a pillow or on a yoga block. For a deeper stretch, lean forward.

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