Pigeon
How to do it
Start on hands and knees. Slide the right knee forward toward the right wrist, then angle the right shin across the mat — the right foot moves toward the left hip if the hips allow, otherwise closer to the right hip. Extend the left leg long straight behind you, with the top of the left foot resting on the floor. Square the hips toward the front of the mat as much as possible. Stay upright with the hands on the floor in front of the right shin, or fold forward over the front leg with the forearms or forehead resting on the floor. Hold, then switch sides.
Why it's good for runners
This is the pose runners default to when their hips hurt, and for good reason: the front-leg position puts the glute, piriformis, and deep external rotators on a deep stretch that little else reaches. These are the tissues that get cranky in the late miles of long runs and after racing on a course with turns or hills. Pigeon is the most efficient direct release for them.
Common mistakes
Don't let the back-leg hip rotate up off the floor — keep the hips as square as possible, even if it means a less-extreme front shin angle. If the front-leg hip lifts way off the floor, fold a blanket or block under it for support. And don't push past sharp knee pain in the front leg — if the front knee complains, walk the front foot closer to the front hip.