Child's Pose with Side Reach
How to do it
Kneel and sit back on the heels with the knees wide, big toes touching. Walk both hands out in front along the floor, lowering the forehead toward the mat — a wide-knee Child's Pose. Walk both hands together over to the right, keeping the hips back on the heels. Feel the long stretch through the left side body and the left lat. Hold and breathe. Walk the hands back through center, then over to the left.
Why it's good for runners
The lats and the side body — quadratus lumborum, obliques — are tissues that running quietly tightens because they stabilize against arm carriage and pelvic motion. Most runners never directly stretch them. This pose puts a heavy weight on the side body and the lats in one shape, with the hips grounded so the stretch can't escape elsewhere.
Common mistakes
Don't let the hips lift off the heels as you walk the hands sideways — the hips stay grounded so the stretch is in the side body, not in a side-leaning torso. And don't grip the floor with the fingers; the hands are just slid along, not gripping.