The Spine Has Four Directions

Flexion, extension, rotation, lateral bend. Every pose in yoga is one of those or a combination of two. Once you can see the four, the repertoire stops being a list of hundreds of shapes and becomes a small number of movements in different orientations.

The four

Flexion — rounding forward. Every forward fold, child's pose, cat, knees to chest, plough.

Extension — arching backwards. Cobra, Upward Dog, Camel, Wheel, Sphinx, Locust, bridge, cow.

Rotation — twisting. Every seated, supine, standing and revolved shape.

Lateral bend — sideways. Side bends, Gate Pose, Triangle in part, Extended Side Angle in part.

How much of each is available, and where

This is the practically useful part, because the answer varies by region and it determines where a movement should happen.

Flexion: available throughout, and most in the lower back and neck.

Extension: substantial in the lower back and neck; limited in the mid-back, restricted by the ribs and by joint orientation. The mid-back is also where extension is lost first by modern life.

Rotation: almost none in the lower back — around five degrees across all five lumbar vertebrae. Moderate in the mid-back, around thirty-five degrees. Most in the neck.

Lateral bend: moderate throughout.

Two facts do most of the work in the whole subject:

The lower back does not rotate. Force it and you load structures that do not tolerate it. A twist belongs in the mid-back.

The mid-back does not extend much, and it is stiff in most people. So the body hinges at the lower back instead, concentrating a backbend into one point.

What this tells you about each category

Forward folds

The fold should come mostly from the hip, not the spine. The pelvis rotates over the femur heads and the spine comes along, long.

The failure: the pelvis does not tip, so the spine rounds to make up the distance. You get closer to your feet and the hamstrings get nothing.

The fix: raise the hips, bend the knees, and learn to tip the pelvis.

Backbends

Extension should be distributed along the whole spine, not hinged at the lower back.

The failure: the mid-back stays flat and the lower back and neck do all of it. Look for a sharp crease at the waist and a flat mid-back.

The fix: draw the lower front ribs down and in, lengthen before bending, and work on mid-back extension separately — passively, over a rolled blanket, daily.

Twists

Rotation belongs in the mid-back.

The failure: cranking with an arm, which sends the force past the mid-back's limit into the lumbar spine and the sacroiliac joint.

The fix: set the pelvis level, lengthen on the inhale, rotate on the exhale, initiate from the lower ribs, let the head go last, and use the arm to maintain rather than to force.

Lateral bends

Both sides should work. The compressed side lengthens too — a side bend is not a collapse.

The failure: dropping into the shape so the lower side folds and the upper side does all the stretching.

The fix: lift up out of the waist before going over. Feel both sides long.

The counter-pose logic

This is why sequences are built the way they are.

Whatever you do a lot of, do a moderate amount of the opposite afterwards.

• Backbends → mild flexion and twists, after a minute's pause, not immediately or aggressively.
• Long forward folding → gentle extension, Sphinx or a supported bridge.
• A strong twist → a symmetrical shape.
• Lateral work → the other side, obviously, and then something symmetrical.

Note the word moderate. The instinct after an extreme is the opposite extreme, and that is wrong — the muscles you just worked hard are the ones you would be stretching immediately afterwards. Pause, then counter gently.

Using it to read an unfamiliar pose

Ask: which of the four is happening, and which region should be producing it?

Revolved Triangle: rotation plus flexion. The rotation belongs in the mid-back, the flexion at the hip. Which immediately tells you the two failures — twisting from the lumbar spine, and folding by rounding the back.

Extended Side Angle: lateral bend plus a little rotation. So both sides of the trunk should be long, and the chest should rotate open, and the failure is collapsing onto the front thigh.

Camel: extension. Distributed, not hinged. Ribs down.

Ten seconds, and you know what the pose wants and where it will go wrong.

Building a balanced practice

A session that visits all four directions in both a warming and a working capacity is a complete spinal practice.

A simple audit: over a week, how many minutes did you spend in each direction?

For most people the answer is heavily weighted to flexion, with some extension, very little rotation, and almost no lateral bend — which mirrors how they spend the rest of their lives, and is exactly backwards from what would help.

Rotation and lateral bend are the two to add, and they are the two most commonly missing.