The driving force of human development, in addition to laziness, is also the pursuit of comfort

Walking on two legs is one of the obvious signs that distinguish us from other animals. Our ancestors went through a structural change in the process of walking on four legs to walking on two legs, and the spine was bent to form a unique "S". When we sit down, the main pressure and support parts of the body become the spine, buttocks and legs. In contrast to the buttocks and legs, which can receive support from the seat, the spine with nowhere to place becomes a short board, and its state becomes an important factor in determining comfort.

When sitting upright, the muscles involved in the force are mainly located in the deep lumbar paraspinal small muscle groups, while when sitting paralyzed, the surface large muscle groups will participate in the force, and the large muscle groups are better at exerting force, so it will make people feel more comfortable to sit paralyzed, but the large muscle groups consume more energy and are more prone to fatigue. After sitting paralyzed for a long time, the muscles are exhausted. When the muscles cannot maintain the stability of the lumbar spine, we are greeted by lumbar muscle strain, ligament overstretching and loss of elasticity, and finally the intervertebral discs are damaged and prolapse in years. Damage to the lumbar intervertebral disc can compress the nerves, causing numbness or severe pain in the limbs, and this damage is irreversible!

The core of making people sit comfortably is to allow the joints of the body to form a specific angle through the slight lowering of the legs and the straightening of the spine, so that the pressure is properly distributed on the intervertebral discs between the vertebrae, and the load is properly and evenly distributed on the muscle tissues. A good office seat or car seat will give the right support to the lower back in the correct position according to the natural curve of the human body, and the car seat will also cushion the vibration through a soft and comfortable seat cushion to prevent discomfort from sitting for a long time. In simple terms, it is in line with ergonomics.

Ergonomics is a multidisciplinary interdisciplinary subject. The core issue of research is the coordination between humans, machines, and the environment in different operations. Research methods and evaluation methods involve psychology, physiology, medicine, anthropometrics, aesthetics, and engineering technology. The purpose of research is to guide the design and transformation of work equipment, work methods, and work environments through the application of knowledge from various disciplines, so that the characteristics of work in terms of efficiency, safety, health, and comfort can be improved.