A literature review of upright sitting posture and its effects on physical and mental conditions

Introduction and research focusWe all sit in different ways and postures, in various types of chairs, and time intervals. But what is an ergonomically sustainable sitting behaviour for people to stay physically and mentally fit during a working life? Can our sitting position affect our alertness, level of stress and/or level of confidence in any way? Are there connections between how we sit and how well we perform at work? These questions are of great interest both for furniture designers and businesses.The purpose of this study was to examine what kind of studies that have been made on upright sitting postures and their effects on health and performance. The aim was to get a deeper understanding on what people perceive as upright sitting postures, how these are obtained and maintained as well as how they affect the users. MethodologyThe study is mainly based on a thorough scientific literature study, but also written newspaper articles, text books and lectures that include topics such as ergonomics, stress, performance, confidence in relation to sitting have been used as data sources. Research outcomesThe first part of the result deals with the definitions of what an upright sitting posture is, as well as how an upright sitting posture is defined. The study also states differences in how people in real working life (such as office work, vehicle driving, control room operations and learning at school) position themselves in various types of office chairs and vehicle seats (car, truck, bus, train, airplane). The study also deals with the differences in how people with various anthropometric measures, age and BMI achieve an upright sitting posture.The second part of the result explores the factors that enhance users to sit upright and investigates how users obtain and maintain that specific posture. When, how and why people make changes in their sitting postures is also dealt with.\ua0 The third part of the results probed if and how the duration of an upright posture affects the users\u27 physical and mental conditions. Muscle activity, blood flow and breathing were the physical factors were connections could be found in relation to upright sitting postures. For the mental conditions connections were found between user’s alertness, level of stress, level of confidence in relation to upright sitting postures.To summarize, how a person obtains and maintains an upright sitting posture depends on several parameters such as the users’ individual measures, type of work tasks, type of chair and its adjustment possibilities. The user’s physical and mental conditions also play an important part. By obtaining and maintaining an upright sitting posture may have positive effects on alertness, confidence and performance