Butterfly

How to do it

Sit on the floor and bring the soles of the feet together, letting the knees fall out to the sides. Hold the feet or the ankles with both hands. If the low back rounds backward as soon as you sit, sit up on the edge of a cushion or a folded blanket. Sit up tall through the spine, then fold forward from the hips as far as is comfortable, letting the upper back round. Feet further from the body makes it gentler; drawing them closer makes it deeper. Stay and breathe.

Why it's good for runners

Running happens in one narrow corridor, forward and back, and the inner thigh is one of the tissues that quietly shortens because nothing ever asks it to lengthen. Butterfly opens the adductors and the front of the hip sockets with no standing balance and no load, which is why it belongs at the end of a session rather than in the middle of one — it is a place to let go, not a place to work.

It is also the first shape in the cool-down where the legs stop holding you up. That transition matters as much as the stretch: the session downshifts here.

Common mistakes

Don't press on the knees. Pushing them toward the floor with the hands turns a hip opener into a strain on the inside of the knee, and the hip does not open any faster for it. Don't insist on a flat back — this is a rounded fold and forcing it straight just stops you folding at all. And don't sit flat on the floor out of pride if your pelvis tips backward; the cushion is what makes the pose work.