Zhaohai (KI6): The Point Below the Inner Ankle for Broken Sleep

Where Zhaohai Sits

This point sits on the inner side of the foot, in the small hollow directly below the inner ankle bone, one thumb's width (about 2 cm) below the bone's highest point.

This line is the deepest of the three that run up the inner leg. The traditional map starts it in the middle of the sole and carries it under the arch to the inner ankle, where it makes a small loop around the ankle bone before climbing the inside of the calf and thigh and the front of the trunk. Vietnamese and Chinese texts call it the Kidney channel. This dip is the sixth stop along it, sitting at the bottom of that loop, directly below the bone.

The old texts place it one proportional unit below the inner ankle bone. Those units scale to your own body, and one of them is about the width of your own thumb at the knuckle. So the instruction becomes easy. Find the highest point of the inner ankle bone, come down one thumb's width, and you are in the small hollow under the bone's lower edge.

Under the skin, the lower edge of the inner ankle bone is anchored by a broad, fan-shaped ligament that holds the ankle steady on its inner side. The tendons of the muscles that hold up the arch and curl the toes run past this spot on their way into the sole. A Vietnamese reference text describes the point lying in the groove between two of those tendons, and suggests turning the sole inward a little to make them stand out. That is a useful trick, and it is used in the finding method below.

The nerve supply explains what you feel. The skin here is served by branches of the saphenous nerve, which carries fibres from the fourth lumbar root of the spine. Deeper, the tibial nerve passes behind the ankle bone and divides into the nerves of the sole. A heavy press slightly too far back can catch one of those branches and send a tingle into the arch or the toes. That feeling means move the tip, not push harder.

Why This Spot

This is an easy point to land on. The ankle bone is the clearest landmark on the inner foot, and the hollow under it is small and well defined. There is little padding. A small, firm tip reaches the sore spot with modest force. And it can be worked sitting on the edge of the bed with the foot on the opposite knee, which is exactly where a before-bed routine happens.

It also sits under a joint that works constantly. The ligament and tendons here steady the ankle every time you shift your weight. In people who have spent decades on their feet, or whose arches have dropped, the small hollow below the inner ankle bone is often tender. Probing it usually finds the sting quickly, which is what this method relies on.

In this tradition the point has a role beyond its own channel. It is counted among the eight confluent points, said to open onto deeper vessels that classical writers believed bound the channels together. Here that vessel is the Yin Heel Vessel, which is said to rise from this point up the inner leg and body to the inner corner of the eye. Its partner, the Yang Heel Vessel, opens from the matching point below the outer ankle bone. In this tradition the two heel vessels are described as governing the opening and closing of the eyes: one linked to waking, one to rest. That is why this small hollow appears again and again when the complaint is a night that will not hold together.

What the Old Texts Say About Zhaohai

The name pictures light on water: the shining sea. The channel starts as a spring in the sole and widens to a stream behind the ankle. Here, gathered in the hollow below the bone, it is pictured as a still, wide sea. Names on the channel map were teaching aids. This one tells students that the point is a gathering place, quiet and deep, rather than a place of movement.

Two classical works are cited for its location in the Vietnamese reference text by Ngô Trung Triều. The first is the Systematic Classic of Acupuncture and Moxibustion, the Jiayi Jing, compiled by Huangfu Mi in the third century. The second is the Classified Classic, the Leijing, by Zhang Jiebin, published in 1624. Both place the point one unit below the inner ankle bone. More than thirteen centuries apart, the two books put the same small hollow in the same place.

The same Vietnamese text lists the point for nervous exhaustion, an irregular monthly cycle and a sore throat, among other complaints. Its finding method is practical: feel for the groove between the two tendons directly under the ankle bone, and ask the person to bend and straighten the foot and tip the sole inward so the tendons show. That is the method you will follow below, adapted for doing it on yourself.

In 2008 the World Health Organization published a single standard for point locations across the Western Pacific region. Its entry places this point on the inner side of the foot, one unit below the prominence of the inner ankle bone, in the depression below it. It adds a note that the corresponding point on the outer side of the foot is the one below the outer ankle bone, the partner described in the next section.

Points That Work With Zhaohai

The closest partner is the mirror point on the outer side of the same foot. Find the outer ankle bone and slide straight down off its lower edge into the small dip between it and the heel bone. In this tradition the two points open the paired heel vessels, one linked to rest and one to waking. Work the inner point first, then the outer, or hold both together with thumb and middle finger and rub gently.

The second partner sits behind the inner ankle bone. From the top of the bone, slide back toward the thick heel tendon and sink into the soft dip halfway between them. It is the main point of the same channel and is commonly used for tired legs and night trips to pass urine. Working behind the bone and then below it covers the whole inner ankle in a couple of minutes.

The third is on the wrist. Turn your hand palm up and run a fingertip along the wrist crease toward the little-finger side. Stop in the small hollow right inside the tendon on that edge. It is commonly used for a mind that will not settle, and because you can reach it lying down, it makes a good last step before you turn out the light.

How to Find and Press Zhaohai

Getting Into Position

Sit on the edge of the bed or a firm chair. Rest the outer side of one ankle on the opposite knee, so the inner ankle faces up and the foot hangs loose. If your hips will not allow that, rest the heel on a low stool and lean forward. Keep the foot relaxed. A foot held stiff pulls the tendons tight across the hollow.

How to Find It

Put a fingertip on the highest point of the inner ankle bone. Slide it straight down over the bone until it falls off the lower edge into a small, soft dip, about one thumb's width below the top. To be sure you are in the right groove, tip the sole of your foot gently inward and back again. You will feel tendons tighten either side of your fingertip. The point sits in the dip between them, right under the bone.

That gives you the area, not yet the point. Now let the foot relax and probe. Take a rounded-tip pressing tool, or the tip of your thumb with the nail cut short, and press small spots around the dip: a little forward, a little back, closer to the bone. Most of it feels like ordinary pressure. One spot will sting, a sharp, pinpoint tenderness. That is the point. Probe fresh each time, because the sore spot can shift a few millimetres from day to day.

How to Press It

Keep the tip on the spot that stings and rub it in small, slow circles, no wider than a grain of rice, without lifting off. Aim slightly upward, toward the underside of the ankle bone, rather than straight down into the foot.

If you use your thumb, wrap your fingers over the top of the foot for support and let the thumb tip circle. If you use a tool, hold it like a pen, close to the tip, so it cannot skid off the bone. To pair it with the outer ankle point, put your thumb tip in this dip and your middle fingertip in the matching dip on the outside, and circle both together.

How Much Pressure

Sharp under the tip is right. That pinpoint sting is the sign that you are on the point, and it should fade within moments of lifting off. Pain that stays after you lift off is not right. Nor is pain that spreads through the foot, or an ankle that turns swollen, hot or red. Stop if any of those happen. Stop too for any electric, tingling or numb feeling running into the arch or toes, which means you are on a nerve branch; move the tip a little and lighten. If you notice you are holding your breath, ease off.

How Long

One to three minutes on each foot. For the first few sessions keep to about a minute a side, because this small hollow can be surprisingly tender. Over the following days, as the sting settles, work up toward two and then three minutes. Do both feet. Once or twice a day is enough, and for most people the evening session is the one that counts.

When to Do It

This point belongs in the evening, in a short routine before bed. Many people in their fifties, sixties and seventies fall asleep without trouble. What goes wrong is the small hours: a hip that aches, a calf that cramps, a bladder that needs emptying, and then a mind that will not settle again. The useful window is before you lie down. Pass urine, sit on the edge of the bed, work this point and its outer partner on each foot, finish with the wrist, then lie down and let the body go heavy. A daytime session is fine too. What this method does not do is press in the middle of the night. If you wake, leave the point alone, keep the light off or low, and let yourself settle.

What This Won't Do

It will not stop you waking in the night, and it will not undo the changes that age brings to sleep. Sleep after fifty is lighter and more broken for most people, and the reasons are many: pain, cramps, a bladder that fills sooner, medicines, worry, a snoring partner. A hollow below the ankle reaches none of those directly. What it offers is a quiet, repeatable routine at the end of the day, which many people find settling, and a few minutes of attention for feet that carry them everywhere. Hold it to that, and it is worth doing.

It will not replace a doctor either. Getting up to pass urine more than twice a night is worth raising with a doctor, particularly if it is new, or comes with burning, blood or a weak stream. Loud snoring with pauses in breathing, waking gasping, or heavy sleepiness in the day need a doctor's view. So does low mood that has lasted weeks, or pain that wakes you every night. Swelling in one ankle or calf only, especially if hot or red, needs to be seen the same day. Time spent pressing is time not spent getting those looked at.

Safety First

Do not work over skin that is broken, infected, badly bruised or rashy. Leave the ankle alone after a fresh sprain, a recent fracture or surgery, or with any plate or screw under the skin. Never press on a bulging vein. If you have varicose veins or have ever had a clot in the leg, ask your doctor before pressing. If you have diabetes or poor feeling in your feet, check the skin of your feet and ankles first and ask your doctor before you start, because you may not feel when pressure is too much. With blood thinners or easy bruising, use the lightest pressure that still finds the sting, and keep sessions short.

Stop at once if the pain stays after you lift off, spreads, or the area turns swollen, hot or red, and stop for any electric or numb feeling. For the full list of cautions and situations where self-applied pressure is not appropriate, read the full safety guide before you begin.

Questions People Ask

Where is the Zhaohai (KI6) pressure point? Zhaohai (KI6), the Shining Sea (Chiếu Hải in Vietnamese), is on the inner side of the foot, directly below the inner ankle bone. Put a fingertip on the highest point of the bone and slide straight down, about one thumb's width, until it drops into a small soft dip under the bone's lower edge. Probe there until one spot stings.

How is Zhaohai (KI6) different from Taixi (KI3)? Both sit around the inner ankle bone, but in different directions. Taixi is behind the bone, halfway to the heel tendon. Zhaohai is directly below the bone. In this tradition Taixi is used more for tired legs and the channel as a whole, and Zhaohai more for nights and the throat. You can work both in the same session.

What is the Zhaohai (KI6) point used for? Zhaohai (KI6), the Shining Sea, is called Chiếu Hải in Vietnamese. In this tradition it is commonly used for nights that break in the small hours, a dry throat on waking and a tired, restless feeling in the evening. Work it for one to three minutes on each foot, before bed or in the daytime. Many people pair it with the matching dip below the outer ankle bone. It is a settling routine, not a replacement for a doctor.

Can Zhaohai (KI6) stop me waking at night? No one can honestly promise that. In this tradition the point is commonly used for broken nights, and many people find a short routine before bed settling. Night waking after fifty has many causes, so if it is new, getting worse, or comes with pain, breathlessness or frequent trips to pass urine, talk to a doctor.

Why not press it when I wake at three in the morning? Because probing for a stinging spot wakes you further. The routine belongs before bed or in the daytime. If you wake in the small hours, keep the light low, stay still and let yourself settle. Save the point for the next evening.

My ankles swell by the evening. Can I still press here? Mild puffiness that goes down overnight is common, and light work on clear skin is usually fine. Swelling in one ankle only, swelling that is hot or red, or swelling that comes with breathlessness is different. Leave the point alone and see a doctor.

Other Points in This Library

Each of these sits within reach of the same hand. They are often worked in the same sitting.

This page shares general information about a traditional practice. It is not medical advice and does not replace what your doctor has given you. If you are pregnant, managing a health condition, or unsure whether this applies to you, check with your doctor first.

The whole inner edge of the foot, laid out on one page with photographs, is in The Foot Map — the free book. For every point in this library, see the full pressure point index.

(Point shown: KI6 · Zhaohai · The Shining Sea · Chiếu Hải.)