The key to sleeping on a mattress is your sleeping position and turning over.

In the `` How to Choose a Pillow '' column, I mentioned that when you are lying on your back using a pillow, the curve of your entire spine is usually a little more gentle than when you are standing. This time, we will consider the relationship between sleeping position and mattress (bedding), as well as turning over in bed.

1. Adjust your sleeping position

Why do people stand on two legs? It's not because your spine supports your upper body. This may be easier to understand if you think of tent poles. The pillars stand because they are pulled from all sides by the campus and ropes, and they do not stand on their own. As the rope loosens, the angle of the post changes. The same goes for your spine. The muscles around your spine pull together to keep your spine erect. When the strength of attraction changes, the posture changes.

So why does the curve of the spine become gentler when lying on your back? When you are standing, your spine rests on top of your pelvis, and your head rests on top of it. Both hands hang from the collarbone, which connects to the spine. The spine is curved in an S-shape to support the heavy upper body. On the other hand, when you lie on your back, your spine is released from vertical gravity. As a result, your back muscles will be a little longer and the S-curve will be shallower than when you are standing.

When does the S-curve become distorted? The human body is made up of four blocks: the head, thorax, buttocks, and legs, and the joints that connect them.The joints can be thought of as the cervical vertebrae, lumbar vertebrae, and leg joints. When you lie down and sleep, your muscles relax and gravity acts on each of the four blocks separately. The heaviest of the four blocks is the butt. It receives approximately 44 % of the total load. Approximately 33 % of the load is applied to the chest, approximately 15 % to the legs, and approximately 8 % to the head.

When you fall asleep, your muscles become sluggish and relaxed. While sleeping, you are unable to support your posture with your own strength, so you must support your body with pillows and bedding. If your body is not properly supported during sleep, your heavy buttocks and chest will drop lower than your head and legs, creating a W-shape. This can increase the burden on your lower back and lead to lower back pain. For these reasons, we do not recommend mattresses that are too fluffy or sag in the center.

2. Ease of turning over

During sleep, we do not stay in the same position until morning, and as we turn over, we usually find a balance between lying on our back and lying on our side.

Turning over in bed helps prevent poor blood circulation in the areas of your body that are under weight. It is also said to play a role in correcting the strained spine caused by daytime activities. Such tossing and turning is a necessary tossing and turning.

On the other hand, if the bedding is too soft, it will become fluffy and make it unstable to maintain your body's posture, causing your muscles to work hard to correct your body and causing you to turn over frequently as you try to change your posture. This may cause you to turn over in bed to correct your posture, and may even wake you up. This type of tossing and turning can be considered unnecessary tossing and turning.

3. Is a firmer mattress better?

So, is it better to use hard bedding? it's not. If you sleep on a flat, hard surface, your butt will lift too much and your lumbar spine won't follow its natural curve. Additionally, body pressure is concentrated in the buttocks, making it difficult for the surrounding muscles to relax and causing a strong feeling of pressure. If muscle tension continues or pressure is strong, tossing and turning will occur more frequently.

During sleep, it is important to sufficiently relax the muscles that maintain your posture during the day, do the necessary tossing and turning, and reduce unnecessary tossing and turning. To do this, you need to support your body without letting the heavy parts of your body sink and without tensing your muscles. It is a good idea to choose a mattress that has moderate cushioning on the top layer and firm support on the bottom layer.

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