Bandhas and mudras are the parts of yoga that sound most esoteric and turn out, on inspection, to be surprisingly concrete. A bandha is a lock — a deliberate muscular contraction that contains and redirects energy. A mudra is a seal — a gesture or hold, often of the hands, that closes a circuit and turns attention inward. Neither is strictly "science," but both have effects the body can feel, and increasingly ones physiology can describe.
They belong with Pranayama because they are applied through the breath — most often during retention — to direct what the breath has gathered.
Bandhas — the locks
Energy locks: directing, containing, and redirecting prana.
In one line: Bandhas are small, deliberate muscle contractions that — in the yogic map — "lock in" energy, and in modern anatomy do real work on the core, pelvic floor, and nervous system.
From tradition
Bandha means lock or seal. Bandhas are specific contractions of muscle groups that, in the yogic framework, create energetic seals within the body — preventing the dissipation of prana (life force) and redirecting it upward through the central channel, Sushumna.
Along that central channel sit three granthis — psychic "knots" that the locks, and Maha Bandha especially, are said to help loosen and pierce. → See The three granthis in Subtle Anatomy.
From science
From an anatomical perspective, bandhas increase intra-abdominal pressure, engage deep core stability, and directly affect the autonomic nervous system through their action on the pelvic floor and abdominal muscles. The contraction of the perineum, for example, corresponds to the sacrococcygeal nerve plexus — a region rich in parasympathetic nerve fibres.
The bridge
The traditional and the anatomical descriptions are not the same thing, but they resonate with each other. What the tradition calls "redirecting prana upward through Sushumna" lines up with what anatomy describes as creating internal pressure and engaging the deep core to support and lengthen the spine. The yogic map names regions and effects that modern physiology is still catching up with — without claiming one framework proves the other.
"The bandhas induce pratyahara (sense withdrawal) and are preliminary techniques for meditation." — Bihar School of Yoga, Asana Pranayama Mudra Bandha
The three main bandhas
Mula Bandha (Root lock) Contraction of the perineal body — the point midway between the anus and the genitals. In women, the equivalent contraction is around the cervix and upper vaginal muscles. This is distinct from the full pelvic floor squeeze or anal contraction (Ashwini Mudra), though those are useful preparatory practices. Mula Bandha is subtle and central. It stimulates the base of the spine, integrates the pelvic floor into the breath cycle, and — in the yogic framework — awakens the dormant energy at Mooladhara chakra. It is practised in three stages: physical only, physical and mental, and finally psychic contraction alone.
Uddiyana Bandha (Abdominal lift) Practised on a full exhale with the breath held outside. The abdomen is drawn sharply back and up toward the spine and under the ribcage, creating a powerful vacuum in the abdominal cavity. This massages the abdominal organs, fires the deep core, and — in the energetic model — stimulates Manipura chakra at the solar plexus. It is an advanced practice, always taught after Mula Bandha is established. Never practise on a full stomach.
Jalandhara Bandha (Throat lock) The chin is drawn down to meet the sternum, lengthening the back of the neck and sealing the throat. Applied during breath retention — particularly after a full inhale — it prevents the premature release of air and regulates the pressure in the chest. In the energetic map it corresponds to Vishuddhi chakra at the throat, and is said to contain the prana gathered on the inhale.
Maha Bandha — the great lock
When all three bandhas are applied simultaneously — Mula, Uddiyana, and Jalandhara — this is Maha Bandha, the great lock. It seals the base, compresses the centre, and contains the top, creating a concentrated internal pressure that, on release, is said to flush prana through the entire body. It is a practice of integration, requiring all three to be established independently first.
Bandhas and the nervous system
The perineal region engaged by Mula Bandha corresponds anatomically to the sacrococcygeal nerve plexus. Repeated engagement and release of the pelvic floor stimulates the parasympathetic nervous system and, over time, develops proprioceptive awareness of a region most people have little conscious access to. The Bihar School notes that Mula Bandha "helps to integrate the neurological and endocrinological functions of the body by manipulation of body energies" — a description that, while rooted in classical yoga, lines up with modern understanding of pelvic floor neurology and its relationship to the autonomic nervous system.
Try this — notice, don't lock
This is the very beginning of Mula Bandha, and the only version a beginner needs. Sit comfortably with a straight spine. Close your eyes and breathe slowly through the nose. Without contracting anything, simply notice what your pelvic floor does during the breath cycle. On a slow inhale, it yields very gently downward. On a slow exhale, it lifts very gently upward. Do this for two minutes. No squeezing, no holding — only awareness. Full Uddiyana Bandha and Maha Bandha are advanced practices learned with a teacher; this gentle noticing is the foundation everything else is built on.
Mudras — the seals
Gestures that close the circuit and turn attention inward.
In one line: Mudras are simple holds — usually of the hands, sometimes of the whole body — that seal a subtle circuit and quietly shape the state of the mind.
From tradition
Mudra means gesture, seal, or mark. Where a bandha contracts and locks, a mudra closes a loop — completing a circuit so that energy circulates rather than leaks away. The hatha yoga texts treat some mudras as among the most powerful practices of all; most are subtle, and the simplest are the hand gestures (hasta mudras) used in meditation and pranayama.
From science
Mudras are the least studied of these techniques, and honest practice means saying so: the evidence is thin. What can be said plainly is that a settled hand position is a quiet anchor for attention — a small, consistent point of contact that helps the mind stay gathered, much as a mantra or the breath does. The lightness of the gesture is the point: it asks for almost nothing, so it does not pull attention outward.
Common hand mudras
Chin Mudra & Jnana Mudra (the gesture of consciousness / of knowledge) The tip of the index finger touches the tip of the thumb; the remaining three fingers extend. Resting on the knees, palms down, it is Chin Mudra; palms up, it is Jnana Mudra. The joined finger and thumb close a gentle circuit — in the tradition the thumb represents universal consciousness and the index finger the individual self, and the gesture quietly unites the two. It is the default hand position for seated breath and meditation practice.
Anjali Mudra (the gesture of offering) The palms pressed lightly together at the heart. A gesture of centring and respect, used to begin and end practice — it draws the two sides of the body, and the attention, into one line.
Dhyana Mudra (the gesture of meditation) The hands rest in the lap, one cupped in the other, thumbs lightly touching to form a closed oval. Associated with deep meditative absorption, it gives the hands a stable, symmetrical home so the body can be forgotten.
A whole-body seal — Shanmukhi Mudra
Some mudras involve the whole face. In Shanmukhi Mudra, the fingers gently close the gateways of the senses — the eyes softly covered, the ears bridged, the lips sealed — turning attention fully inward. Practised alongside Bhramari (humming bee breath), it keeps the humming inside the skull and is one of the most direct bridges from Pranayama into Pratyahara, the withdrawal of the senses.
Try this — Chin Mudra for ten breaths
Sit comfortably. Rest your hands on your knees, palms down, and lightly touch the tip of each index finger to the tip of each thumb — no pressure, just contact. Let the other fingers fall naturally. Take ten slow breaths through the nose, with your attention resting where finger and thumb meet. That small, closed circuit is enough to keep the mind from wandering far. This is the whole practice: a quiet anchor that asks almost nothing.
Cross-references
Pranayama · Asana · Pratyahara · Dharana · Subtle Anatomy
Sources
- Bihar School of Yoga — Asana Pranayama Mudra Bandha
- B.K.S. Iyengar — Light on Pranayama
- Santosh — Yogadarshanam (300H YTT)
- Patanjali — Yoga Sutras