Straighten your back!

Why we sit incorrectly and how it affects our health

Anna Kalinina, N+1

In total, about 8.9 percent of adults spend less than 4 hours a day sitting, while 20.6 percent spend 12 hours or more. Over the past 10 years, the number of publications about the harm caused to the body by a sedentary lifestyle has increased 17 times. But the problem is not only that we spend a lot of time sitting — most often we also do it wrong. In the partner material that we have prepared together with Cougar, we tell you what a sedentary lifestyle threatens the body, what it means to "sit properly" and how to help yourself keep your body in a healthy position.

Squatting Life

Reducing energy consumption is often considered a key goal of natural selection. For humans, walking on two legs turned out to be 75 percent less energy-consuming than walking four-legged monkeys and even two-legged chimpanzees. This is explained anatomically: compared to monkeys, humans have a more elongated hip and long hind limbs. However, an even greater reduction in energy consumption in a sitting position is no longer an evolutionary advantage, but, on the contrary, is associated with a health risk.

Man in the process of evolution has adapted to long-distance transitions and an active lifestyle during hunting, allowing himself to lie or sit during a short rest. Our ancestors not only led a more active lifestyle, but also sat differently: on solid ground, cross-legged, on their knees, leaning on their side or even squatting — like the Hadza people living in Tanzania.

In this position, they spend about ten hours a day, but do not suffer from diseases that are associated with a sedentary lifestyle today. Squatting, the hadza can relax, socialize and eat. At this moment, they have increased muscle activity of the legs and back, so this pose cannot be equated with resting in a comfortable chair.

The people of the Hadza people spend most of their time squatting. In this position, they eat, rest and communicate.

Not everyone will be able to sit for as long with their heels flat on the floor. When a child has been squatting since childhood, his body — the hip and knee joints, the Achilles tendon, the muscles of the thigh, buttocks and abdomen — adapts to this. Most modern people are used to sitting on chairs from an early age, and they do not have such an adaptation. Therefore, if we try to squat down, we will not be able to achieve a stable position — we will have to lift the heel off the floor, and this will lead to tension in the legs.

Does this mean that sitting the way we used to is necessarily harmful? Not at all: the problem lies in the fact that a modern person sits a lot and most often incorrectly.

We've been sitting too long

People started spending significantly more time sitting after the Industrial Revolution, when office workers began to dominate the labor market. In 1953, British scientists came to the conclusion that bus drivers and office workers are more likely to suffer from coronary heart disease than representatives of other professions.

Initially, the chair was rather a prestigious and status attribute, although the first available chairs began to be made in the XVIII century. With the advent of office work, companies needed cheap furniture that allows them to be in a sitting position for a long time with minimal harm to health. Comfortable office chairs became widespread at the beginning of the XX century, but it was only at the end of the century that the concept of an "ergonomic chair" appeared.

Recently, computer ergonomic chairs have been gaining more and more popularity. The technologies used in such furniture are rooted in the research of NASA specialists, who in the 1980s developed the basic principles of ergonomics, observing astronauts in microgravity. Later, their findings were tested by car manufacturers, in which people, as well as at the desk, can spend long hours.

Car seats became comfortable and safe for posture and eventually served as the basis for the first gaming computer chair, which appeared in 2006. Today, furniture, once created with an eye to gamers and esports, is increasingly used in everyday life, especially in connection with the relocation of employees to remote work.

Since then, the number of studies devoted to this problem has only increased. However, it was only in 2012 that the Sedentary Behavior Research Organization published a letter defining sedentary behavior — this is the name of any waking activity that requires energy expenditure within 1.5 units relative to basic metabolism, performed in a sitting or reclining position.

Basic metabolism is the energy that the human body burns at rest. It is spent on maintaining all vital processes, such as respiration or blood circulation, and is measured in metabolic equivalents (ME).

ME is defined as caloric intake during activity compared to the baseline resting metabolic rate. One ME is defined as 1 kilocalory per kilogram per hour and represents a person's caloric intake at rest. So, 2 ME will correspond to an activity that is twice the metabolic rate at rest. Sleep corresponds to 0.9 ME, classes from 2 to 4 ME (light walking, house cleaning, and so on) they are considered light, while running or climbing can give 10 ME or more.

It is necessary to distinguish between "sedentary" and "sedentary" behavior. With a sedentary lifestyle, people demonstrate an insufficient level of moderate (3-6 ME) or intense (>6 ME) physical activity, while with sedentary behavior — a high level of sedentary physical activity. In other words, a sedentary lifestyle implies sedentary, but not vice versa.

Sitting posture does not require high energy consumption: when we do not change the body position for a long time, our metabolic rate decreases. Muscles, being the basis for maintaining posture and movement, are the main consumer of glucose and free fatty acids (the main sources of energy), which are needed for the production of ATP (energy molecules) in the body. When muscle contraction is weakened for a long time, the activity of the lipoprotein lipase enzyme decreases, which breaks down triglycerides to fatty acids, leads to the formation of "good cholesterol" and a decrease in glucose uptake by muscles. Excess lipids and glucose, in turn, leads to insulin resistance and inflammation, the development of type II diabetes, atherosclerosis and hypertension.

Moreover, sedentary behavior can affect the body at the gene level. It leads to a decrease in the expression of genes of muscle energy stations (mitochondria) and genes necessary for the synthesis of ATP. It is also known that due to a sedentary lifestyle, the expression of a gene that breaks down muscle proteins increases. Over time, this can lead to muscle atrophy.

Prolonged sitting in a sitting position is considered a risk factor for various diseases. It is known that tissue compression leads to metabolic and hormonal disorders, and the mechanisms of development of carcinogenesis and cognitive impairment have not yet been established.

Weakened muscles cannot support the spine in its natural position. This causes osteochondrosis, intercostal neuralgia, protrusions in the spine — everything that fits the definition of "back pain". And when a person is tormented by chronic pain, it becomes even more difficult to maintain posture. Thus, the load on the pelvis, tendons and joints, bones and intervertebral discs increases.

Bent double

It is especially difficult to maintain posture if we are not used to following it since childhood. The muscles of the back are not trained, so it seems uncomfortable to sit straight. In addition, most often our attention is focused on something other than the position of our own body. In a study published in the journal Physical Therapy, healthy participants who were put at computers by scientists began to slouch after 10 minutes. In the same study, it was shown that people with chronic neck pain slouch more, and a special exercise program aimed at training the cranial flexor muscles helped them to cope with this habit.

Another group of researchers, whose results are published in the journal Manual Therapy, came to the conclusion that in order to maintain vertical posture, a person needs constant visual and verbal reminder. This problem occupies a significant place in research on pose recognition using automated systems that fix the wrong pose in an office environment. Thanks to the automated approach, many may be able to avoid health problems due to improper posture.

Which pose is considered the healthiest?

If you believe the general recommendations, a person needs to sit without tilting his head and upper half of his body forward, relaxing his shoulders and wrists, and keeping his hands and forearms at the same level. Elbows should be kept as close to the body as possible. In this position, the load on the musculoskeletal system is evenly distributed. The legs can be placed on a special stand or on the floor without crossing, and the back and hips should be supported by a chair. It is recommended to place the computer screen at eye level so as not to create additional stress on the neck and shoulders.

Recommended body position while working at the computer.

However, scientists did not agree on all issues. For example, some studies have indeed shown that in people with neck pain, an increase in unpleasant sensations is associated with a forward tilt of the head in older age groups, while in others, on the contrary, the position of the head does not correlate with the frequency of neck pain in adolescents and older people over 50 years old.

The same applies to back pain. A recent systematic review published in the Journal of Biomechanics found no connection between slouching and the occurrence of pain, as well as any other lumbar posture and pain. In another study, researchers interviewed people with lower back pain to get their opinion on how best to sit. The most preferred poses were those with the preservation of vertical posture, which are believed to maintain the correct position of the head, neck and shoulders.

A chair to help

Anyone who spends a lot of time sitting should think about ergonomic furniture. It adjusts to the individual characteristics of a person, helps to maintain the correct body position and minimizes the consequences of a sedentary lifestyle.

How does it work?

First of all, an ergonomic chair is selected taking into account the height and weight of a person. Its back supports the lumbar and cervical bends in such a way that the spine is in a natural S-shape. This reduces the load on the intervertebral discs. The high backrest and pillows help to remove the load from the neck, which act as stops for the lower back and neck and are fixed with special clamps. In addition, ergonomic chairs have side stops. They do not allow a person to "hang out" to the sides and slouch.

The adjustable seat height allows the legs to stand flat on the floor, and the monitor to be at eye level. As a rule, the armrests of such chairs are adjustable not only in height, but also move forward and backward, and in some models even rotate relative to the attachment point. This reduces tension in the upper body, as the shoulders and hands are in a relaxed position. Some models of chairs deviate by 90-180 degrees. Thanks to this, you can change your position and take a break.

The ergonomic chair is designed to fix the natural position of a person for a long time, without leading to discomfort and reducing the likelihood of curvature of posture in the future. Usually ergonomic furniture is recommended for people with minor disorders of the musculoskeletal system and vision. It is often confused with orthopedic, but such furniture is designed for people with serious back diseases or, for example, who have suffered a spinal injury.

In addition to ergonomic chairs, there are other furniture designed to preserve the health of the back. For example, a knee chair that compensates for the load on the spine and helps to form the correct posture, but gives a load on the knees and shins. Or a saddle chair that helps strengthen the back muscles and maintains a healthy posture for the lumbo-pelvic and cervical departments. In a study published in the European Spine Journal, scientists compared four types of chairs: an office chair, a saddle chair, a knee chair and a dynamic chair with a movable seat (swopper chair). Apparently, none of them provides perfect posture in all regions of the spine, and the choice should be based on the individual needs of the person.

Ergonomic Cougar computer chairs are equally suitable for those who want to relax and work comfortably. They are equipped with adjustable armrests, side stops, as well as two pads, one of which is placed under the lower back, and the other between the back of the head and neck. Chairs help to maintain correct posture for a long time, support the lumbar and cervical bends of the spine and relieve the shoulders and hands. All Cougar chairs can be expanded 180 degrees to lie down and additionally relieve a tired back.

When choosing a chair, all the most important criteria are taken into account: the height and weight of a person, the average duration of work at the computer, as well as the necessary degree of mobility.

It's time to move

In order to reduce the harmful effects of a sedentary lifestyle on the body, it is necessary to develop useful habits: from time to time change your posture, do not forget about good lighting, take breaks and warm up while working, play sports (in particular, train your back muscles) and pick up comfortable furniture that will help maintain the spine in the right position.

WHO recommends 150-300 minutes of moderate or 75-150 minutes of intense physical activity per week for adults. Moderate exercise includes brisk walking, yoga, swimming, dancing, and intensive — running, cycling, uphill, team sports. The updated WHO guideline has recommendations for all age groups. Any physical activity is better than its absence. Therefore, if for some reason you cannot exercise, ordinary walks and even cleaning will be useful.

It is enough to start with at least a couple of minutes a day. Studies show that regular short physical activity, such as 2 minutes of exercise for every 20-30 minutes of still time, will bring more benefits than an hour of intense exercise after an 8-hour workday. Due to short periods of activity, the expression of 75 genes changes, in particular anti-inflammatory enzymes and proteins involved in the metabolism of carbohydrates, which are necessary for muscle growth and development.

Approximately 5 million deaths annually are associated with a lack of sufficient physical activity. The World Health Organization (WHO) identifies a sedentary lifestyle, or inactivity, as the fourth leading risk factor for mortality. Sedentary behavior can lead to the development of diseases of the cardiovascular system, diabetes, certain types of cancer, depression and sleep disorders. If at the same time you use furniture that is not designed for prolonged sitting, the occurrence of chronic diseases is inevitable. Ergonomic furniture not only supports the body in a natural position, but also helps to change the pose due to adjustable details.

During work, both an ergonomic chair and a height-adjustable table that can be used for standing work can help to change the position. Some studies claim that this increases physical activity and energy consumption. However, the question of how much this helps in the long run remains open. Prolonged standing is defined by 1.59 ME — this is close to the upper limit of a sedentary lifestyle. In the standing position, other muscle groups tense up, and the spine is at a different angle.

General recommendations:

Take short regular breaks (1-2 minutes) with intense physical activity every 20-30 minutes of work. Change your body position as often as possible.
Stretch your muscles from time to time to relieve muscle tension. Learn to pay attention to your posture every 30 minutes (at first, use reminders to form a habit).
Choose for yourself comfortable ergonomic furniture that will support the lower back and neck.
Keep your feet flat on the floor or on a special stand, without crossing your legs. Keep your elbows on the support and close to the body. Relax your wrist from time to time if you are working at a computer.

Despite the fact that Soidag products are designed for the gaming segment, they will be useful for everyone who wants to maintain a comfortable body posture, relieve stress from the lower back, neck and muscles. In addition to the chairs, the range includes a Cougar E-MARS computer table with electric height adjustment and four memory settings, with which you can change the height of the table — this allows you to work comfortably standing up.

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