Janu Sirshasana (Head-to-Knee Forward Bend)

Janu Sirshasana — from janu (knee), sirsha (head), and asana (posture) — is the Head-to-Knee Forward Bend, a seated forward fold in which one leg is extended and the other is bent with the foot pressed against the inner thigh of the extended leg. The forehead (ideally) reaches toward the knee of the extended leg, creating an asymmetric forward fold that stretches the hamstrings and spine while simultaneously creating a mild rotation of the torso toward the extended side. It is one of the most important seated forward bends in the classical Hatha Yoga system.

The Asymmetric Forward Fold

Unlike Paschimottanasana (both legs extended), Janu Sirshasana extends only one leg and bends the other. This asymmetry creates several important differences: the pelvis tilts slightly toward the extended-leg side, making it easier to achieve anterior pelvic tilt (the correct mechanism for forward folding); the bent-leg hip rotates externally, releasing the piriformis and deep hip external rotators; and the mild torso rotation toward the extended leg provides an additional spinal mobilisation not available in symmetrical forward bends. Many practitioners find it easier to achieve a deep forward fold in Janu Sirshasana than in the full Paschimottanasana.

Technique

Steps

1. Sit with both legs extended (Dandasana). Bend the right knee and place the right foot against the inner left thigh — the right knee resting on or near the floor.
2. Inhale and lengthen the spine as tall as possible — rotate the torso slightly toward the left (extended) leg.
3. Exhale and fold forward over the extended leg, leading with the chest rather than the forehead. The movement initiates at the hip joint (anterior pelvic tilt), not at the waist.
4. Reach the hands to the foot, ankle, or shin of the extended leg — wherever they can reach without rounding the lower back excessively.
5. With each inhalation, lengthen the spine. With each exhalation, allow the fold to deepen naturally. Do not use the arms to pull the body down aggressively.
6. Hold 1–3 minutes. Come up on an inhalation, leading with the chest. Repeat on the other side.

Benefits

• Stretches the hamstrings thoroughly: The single-leg forward fold allows the hamstrings of the extended leg to release progressively without the competing tension of the second leg.
• Releases the piriformis and deep hip rotators: The bent-leg position in Janu Sirshasana provides a direct stretch to the deep hip external rotators that are notoriously tight in people who sit regularly.
• Massages the abdominal organs: The compression of the abdomen against the thigh in the forward fold stimulates the liver and digestive organs.
• Calms the nervous system: Forward bending postures activate the parasympathetic nervous system — the prolonged hold of Janu Sirshasana is a highly effective calming practice for anxiety and mental overactivation.
• Stretches the spinal muscles: The forward fold lengthens the erector spinae and quadratus lumborum along the full length of the spine.

Contraindications

• Knee injury on the bent-leg side — ensure the knee is supported and does not cause discomfort in external rotation.
• Hamstring tear (acute or recent) — avoid pulling into discomfort at the sitting bone-hamstring attachment.
• Lumbar disc herniation — maintain lumbar curve rather than rounding aggressively into the fold.

Common Mistakes

The most pervasive mistake in Janu Sirshasana — as in all forward bends — is leading with the forehead (rounding the spine) rather than leading with the chest (hinging at the hip). A rounded back compresses the lumbar discs and reduces the hamstring stretch. Sit on a folded blanket to tilt the pelvis forward if needed. Another common error is allowing the extended-leg knee to bend — the kneecap should press toward the floor, the quadriceps engaged throughout to keep the leg straight.