Adult head weight is about 5 kg, the figure of the force arm of the head gravity, about 2/5 of the head length, about 8.8 cm. The force arm of neck traction can be calculated from the length and angle.

According to the formula, what value of force is applied to the actor's neck? The result of the calculation is that the actor's neck was subjected to a force of about 80 Nm in this sleeping position, which is equivalent to a weight of 8 kg and 16 bottles of 500 ml mineral water hanging from the neck!

Improper sleeping posture, will trigger a variety of diseases
"The cervical spine is the body's most 'valuable' part, bearing the skull, the lower trunk, play a 'bearer' role. Therefore, once the cervical spine problems, if you do not pay attention to it, may even involve other parts." Doctor Wu Lianguo said that improper sleeping posture can induce diseases like cervical spondylosis, high blood pressure, cardiac arrhythmia, gastric diseases and other diseases.

"Sleeping postures like those of the actors in the drama, where 'the neck is empty and the muscles are tense,' can easily induce cervical spondylosis." Wu Lianguo said, this sleeping position is equivalent to the pillow only half of the sleep, will keep the neck suspended, stiff state, the cervical spine is not supported, is not conducive to maintaining the normal physiological curvature.

There are sleeping positions that are signaled by disease
"There are sleeping positions may suggest that the cervical spine has problems." Wu Lianguo said, for example, "surrender posture", put your hand above your head, this is due to the soft tissues of the neck and shoulders are too tense, put your hand up in order to alleviate the muscle tension, blood circulation slowed down caused by the difficulty of falling asleep.

"Some people wake up in the morning, the head is not on the pillow, repeated pillow, feel more comfortable sleeping on their stomachs, the more tired they are, or waking up with a tight neck, like to use high pillows, etc., are because of the continuous tension and spasm of the neck muscles, or sprains, deformations, or lesions caused by." Wu Lianguo said.

This is the correct sleeping position
From the cervical spine health, the correct sleeping position requires both to maintain the normal physiological curvature of the cervical spine, but also to ensure that the whole body muscles, ligaments and other soft tissues naturally relaxed. The best sleeping position is lying on the back, which can best maintain the natural curvature of the cervical spine.

"When lying on your back, you can put a cushion on each of your neck, waist, and popliteal fossa of your knee joints so that you can better support the curvature and allow your muscles to relax." Wu Lianguo said that people who are accustomed to sleeping in the side position can clip a quilt or pillow between their legs, and the pillow should be the same height as the shoulder, and they need to sleep on both sides for a change, avoiding long-term unilateral sleep, or else they are prone to scoliosis.