The name, head-to-knee forward bend, comes from the fact that if the body’s flexibility allows, the whole of the torso will fold over the outstretched leg, with the head touching the knee or going beyond the knee, depending on the individual’s body proportions and flexibility. As a result, it is sometimes called head-beyond-the-knee pose.
The asymmetry of the pose means that as well as being a forward bend, it also provides a slight spinal twist as the spine rotates to fold over the straight leg. Head-to-knee forward bend A is a good pose for creating the flexibility needed to progress into seated forward bend pose, where both legs are straight.
In addition to stretching the hamstrings, it is also said to stimulate the kidneys and liver. The digestive system benefits because this pose stretches both the ascending and descending colon. It may be helpful for those suffering with headaches, fatigue or menstrual pains. However, it should be avoided by anyone suffering from asthma, digestive or lower back issues.
This pose can be modified by sitting on blankets to lift the hips or by placing blankets under the knee of the outstretched leg if tight hamstrings or knee pain is an issue. A belt may be looped around the outstretched foot to help draw the body forward. For those with more flexibility, the hands can clasp the edges of the foot or one hand can clasp the opposite wrist around the sole of the foot, with the head moving onto the shin.