Review of Measuring Microenvironmental Changes at the Body–Seat Interface and the Relationship between Object Measurement and Subjective Evaluation

Abstract

Being seated has increasingly pervaded both working and leisure lifestyles, with development of more comfortable seating surfaces dependent on feedback from subjective questionnaires and design aesthetics. As a consequence, research has become focused on how to objectively resolve factors that might underpin comfort and discomfort. This review summarizes objective methods of measuring the microenvironmental changes at the body–seat interface and examines the relationship between objective measurement and subjective sensation. From the perspective of physical parameters, pressure detection accounted for nearly two thirds (37/54) of the publications, followed by microclimatic information (temperature and relative humidity: 18/54): it is to be noted that one article included both microclimate and pressure measurements and was placed into both categories. In fact, accumulated temperature and relative humidity at the body–seat interface have similarly negative effects on prolonged sitting to that of unrelieved pressure. Another interesting finding was the correlation between objective measurement and subjective evaluation; however, the validity of this may be called into question because of the differences in experiment design between studies.

A Single Subject, Feasibility Study of Using a Non-Contact Measurement to “Visualize” Temperature at Body-Seat Interface

“…However, unobserved thermal accumulation at the body-seat interface has a strong bearing on skin tissue integrity [ 4 , 5 , 6 ], by increasing metabolic demand at a time when there is a decreased blood supply due to tissue compression [ 7 , 8 ]. As a result of the above, friction and shear force are more prone to cause tissue damage, eventually resulting in a breach in the integrity of the skin (ulceration) [ 9 , 10 ]. In males, a temperature increase at the body-seat interface can additionally lead to the deterioration of semen quality and quantity as well as sperm chromatin structure [ 11 ].…”

“…In addition, some perceptions are difficult to exactly delineate, such as thermal comfort or discomfort of a particular body part, unless extreme. As a result, such studies are likely to require large populations to be investigated over prolonged durations in order to arrive at a firm conclusion [ 10 ]. To overcome the inherent drawbacks of subjective evaluations, researchers have increasingly focused on the applicability of objective methods.…”

Changes in external ischial tuberosity width at varying trunk–thigh angles between sexes using two measurement methods

“…Generally, X-ray is the most effective tool for measuring the distance between human ITs 7 . The ITs provide the primary support for the body weight during sitting, however, they do not have direct contact with the seat surface because they are separated by the muscle and adipose tissue that cover the pelvis 8 – 11 . The buttocks comprise the gluteus maximus and medius muscles, on which a layer of adipose tissue is superimposed and enable primates to sit comfortably.…”

“…The buttocks comprise the gluteus maximus and medius muscles, on which a layer of adipose tissue is superimposed and enable primates to sit comfortably. Studies have focused on the complex changes in these subcutaneous tissues between the IT and the seat surface 8 – 11 . Understanding these changes how to influence the external IT width (EITW, Fig.…”

“…Understanding these changes how to influence the external IT width (EITW, Fig. 1 has practical benefits for the design of seat cushions for bicycles and wheelchairs and in various other contexts 8 , 10 , 12 , 13 .

Figure 1 Schematic of the external ischial tuberosity width (EITW).

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