In this pose, gravity should do the work. People experiencing tightness in the back of the legs sometimes pull themselves down, which creates tightness and congestion in the rectus femoris and psoas. It’s better to soften the knees to find some space in the hip joint, allowing the spine to release. Only then does lengthening the legs produce an even stretch along the entire backline of the body.

The seated position paschimottanasana.