Movement as a health factor in seating furniture

Ergonomics in transition: From static to dynamic

The relationship between the body and furniture is a widely studied topic and can be understood as part of the larger concept of "ergonomics." The term was defined in 1949 and is derived from the Greek "ergon," meaning "work," and "nomos," meaning "natural law". Ergonomics describes the study of the relationship between humans and their work environment.

"Over the last two centuries, industrialization has led to physical inactivity and increased sitting for more and more people," explains Norwegian furniture designer Peter Opsvik, who plays a key role in modern ergonomic chair design. (2008, p. 7) Consequently, the effect that a sedentary working life can have on the body has received much attention and has been the subject of numerous studies and research projects.

As a result, since the 1980s, various approaches to ergonomics and how best to ensure healthy sitting have emerged. Today, the widely held opinion is that there is an ideal sitting posture, the "right angle" or "physiological neutral position", which, according to physiotherapist Alexandra Gauster, is known for "causing the least mechanical stress on our bones and structures such as muscles, ligaments, tendons and joints".

In contrast, the second theory is based on the idea that the body is not designed to stand still and therefore a constant change of posture is more beneficial to our health.

Galen Cranz, professor of architecture at the University of California, Berkeley, explains it this way: "Another feature of our bodies is that mechanical stability is not built in. The human body is a dynamic system that cannot stop, so we cannot find a point of complete rest. Since we do not have flat spots in our joints that can be aligned to lock together, which could free the muscles from any work, this means for chair design that the ergonomic search for a position of 'non-work' must be rejected" (1998, p. 130).

Peter Opsvik summarizes the human need for variety when sitting in the phrase “the best posture is always the next one” and draws a comparison to sleeping behavior, in which we regularly change position (2008, p. 37).

Even major players in the furniture industry like Herman Miller support the same view. Their research found that people change position an average of 53 times per hour when they are sitting. And when their chairs are inflexible, people tend to be less engrossed in their work over time (Bernard, 2016, p. 38).

Negative effects of postural fixation

Galen Cranz points out in her book The Chair: "If people are 'unstable' because they move around a lot, chairs should support that movement." She even goes so far as to say: "Chairs that don't offer that flexibility can harm our bodies" (1998, p. 95).

She highlights the potential negative effects of focusing on one posture only by quoting A. Grieco, director of the Institute of Occupational Medicine in Milan, who concludes that ergonomic furniture itself contributes to a new problem, postural fixation. According to him, ergonomic furniture has caused back problems because it supports the body too well in one position (Cranz, 1998, p. 105).

Alexandra Gauster explains the physiological effects of postural fixation as follows: "Even if you sit in a neutral position, there is still a significant load on the system, which can harm the body if maintained all day. Without movement, our muscles become tired and tense. During movement, blood supply is enabled and circulation is stimulated."

Dieter Breithecker, founder of the German Federal Working Group for Posture and Movement Promotion, tells the story from a student's perspective, emphasizing the important relationship between physical and mental activity. "Combined with the static design of most school furniture, students are deprived of critical physical and sensory experiences that are essential for physical and mental growth. Inactive sitting places greater stress on the tissues and systems of developing bodies. Students forced to remain still in a physically static environment become more uncomfortable, tired, and less productive" (2015).

Literature
Galley, M. (no date) “50 Years of Ergonomics – Where have we been and where are we going?”
Opsvik, P. (2008) Rethinking sitting. Oslo: Gaidaros Forlag AS. Cranz, G. (1998) The chair: rethinking culture, body, and design. New York ; London: WW Norton.
Bernard, M. (2016) ‘Active Sitting for Engaged Comfort’, Contract, 57(6), pp. 38–38. Breithecker, D. (2015) body in motion, brains in motion. VS AMERICA, INC.