SUFFERING a stiff neck after waking up in the morning, 30-year-old Cindy Liang had no choice but to turn to tuina (TCM massage) for relief.

Though much refreshed by the treatment, Liang was warned that her cervical vertebra was out of alignment. Poor sleep posture is often attributed to such problems. In Liang’s case, according to her physician, she must have slept at an awkward angle on a pillow that did not support her neck.

It is widely acknowledged that keeping the back straight while standing, walking and sitting is important to preventing back pain. Yet, few are aware that one's sleeping posture also plays an important role in overall health, says Dr Jiang Zaifeng, a registered TCM physician based in Hong Kong.

Energy and blood circulation is the foundation of health, according to TCM. A healthy sleeping position can help ensure smooth blood and energy flows throughout the night, and thus relieve fatigue and increase energy during one's waking hours.

“The ideal sleeping position is one that is comfortable, keeps the spinal column straight and does not obstruct energy flows to any part of the body,” says Dr Jiang. “But, of course, this is not entirely feasible as we live on a planet with gravity. We always have to obstruct or suppress some part of the body when we lie in bed.”

A relatively firm bed is typically recommended for juveniles and those with back problems. Soft mattresses usually cannot keep the spinal column in a straight position. They may cause, or aggravate, spinal problems for growing youngsters. An appropriately thick pillow is also necessary to keep the neck in a comfortable, healthy posture.

In general, most people sleep in one of three positions — on their back, their stomach, or their side. Each choice has its own benefits and disadvantages. There is no need to intentionally keep one position throughout the night, as changing positions several times can help relieve fatigue and pressure.

“Most modern people have to lower their heads for typing and reading during the day. In that case, I would suggest they do the opposite at night,” says Dr Jiang, who suggests raising the head during sleep. One can tilt the head at an obtuse angle from the trunk of the body while sleeping on one's side. A small pillow under the neck can also tilt the head back when sleeping on one's back.

Though being comfortable is the top concern for sleep, there are ways to help every sleeper find a more suitable position.

Sleeping on the back

Sleeping on the back is one of the most common positions. It is said that about 60 percent of people choose this position while sleeping. Yet, many experts discourage this position, as the sleeper's muscles may not be sufficiently rested during the night. Also, it can lead to breathing difficulties.

The position is called shi wo (literally "sleep like a dead body") in TCM. People who sleep on their backs should keep their body and limbs straight so as to relax the tendons and muscles.

Additionally, the root of the tongue tends to fall backward and possibly block the throat when people are sleeping on their back. This can lead to fitful sleep and discomfort in the chest. In some rare cases, sleepers can wake up choking on their own saliva.

“People who sleep on their backs often snore, as blocked breathing passages are a major trigger for snoring,” says Dr Jiang.

Sleeping on the chest

Sleeping on the stomach has been promoted over recent years by several Japanese physicians, including professor Marukawa Seishiro, a specialist in respiration physiology.

In the late 1980s, Seishiro discovered that his patients who slept on their stomachs had generally higher oxygen levels. He began using this posture as part of a therapy for patients suffering from respiratory failure and reported positive results. According to Seishiro, sleeping on the stomach keeps the throat clear of phlegm, saliva and the tongue.

The position can be a good choice for those with breathing problems and those who snore.

Yet, while sleeping on the stomach may ease respiratory discomfort, it also puts greater pressure to the chest and heart, according to Dr Jiang. This pressure may obstruct blood and energy circulation and thus cause chest pains. Those with high blood pressure, heart problems and cerebral thrombosis should not sleep on their stomachs.

And since stomach-sleepers have to twist their heads to one side, this position may also lead to neck pains.

Professor Seishiro provided some solutions to these problem in his book “Healthy Method: Sleep on the Chest.” These included placing pillows between the body and the mattress to keep the spinal column aligned. This method also helps reduce pressure on the chest.

Sleep on the side

The classic Tang Dynasty (618-907) TCM treatise “Qian Jin Yao Fang” (literally "Prescriptions Worth a Thousand in Gold") identified sleeping on the side as the ideal sleeping position. Specifically, the position was described as sleeping partly on the side with bent knees. It can relax muscles and promote energy and blood flows, two things TCM practitioners seek.

Generally, sleeping on the right side is recommended over the left side, according to Dr Jiang. As both the heart and stomach are at the left side of the body, sleeping on the right side will place the two organs at a higher elevation, with less pressure.

Foods in the stomach can naturally move to the intestines while sleeping with the help of gravity, and good blood circulation is also possible. In addition, this position can also aid the flow of bile and thus prevent or relieve inflammations or stones in the gallbladder.

But this "ideal" position may not be suitable for patients with emphysema or other serious breathing problems, as it may compress the lungs. Patients with stomach ulcers are advised to sleep on the left side, since this position will put the stomach below the esophagus and thus prevent acid reflux.

Dr Jiang also warns against putting one's full body weight completely on one side throughout the night, as this will obstacle blood and energy movement on that side and lead to energy "stagnation" over the long run. Patients with hardening blood vessels and thrombus problems should be especially cautious.

Advice for people with specific health problems

Though sleeping on the right side is recommended for most people, this advice may not hold for those with certain health problems.

• Patients with emphysema – sleep on the back with a relatively high pillow to ease breathing.

• Patients with otitis media suppurativa (inflammation in the ear) – sleep on the side with the afflicted ear, as this can help lead to healthy secretions during the night.

• Patients with heart disease – sleep partly on the right side. Avoid sleeping on the chest or the left side.

• Patients with high blood pressure – sleep partly on the right side and remember to place the head relatively high.

• Patients with a sour back – sleep partly on one side with pillows to help keep the spinal column straight.

• Women in late pregnancy – sleep on the left side. With the growth of fetus, the uterus may put pressure to the artery below. Sleeping on the left side can reduce this pressure and promote blood flow to the uterus and thus prevent possible prevent dizziness, vomiting and sweating.

• Patients with edema in the legs – set a pillow under the leg so as to elevate them.