Pin the shin, melt the quad and hip flexor.
Squeeze the glute on the stretching side and keep your torso upright to protect the low back.
The couch stretch attacks the front of the hip and the quad one leg at a time, pinning the shin vertical so the rectus femoris, which crosses both hip and knee, gets lengthened at both joints simultaneously. Sitting all day shortens exactly this tissue, which then quietly robs your squat depth and hip extension. A few minutes per side, done regularly, buys back range most lifters have lost without noticing.
It stretches the quad and hip flexor over two joints at once, knee fully bent and hip extending, which almost nothing in daily life ever asks for. The intensity fades fast with consistency, so ease in and breathe.
One to two minutes per side is a solid dose. Short aggressive holds just make you brace against the position, while longer relaxed breathing is what actually lets it change.
You are arching to fake the range. Squeeze the glute on the stretching side, tuck your pelvis slightly and stay tall. The stretch should live in the front of your hip and thigh, not your spine.
