Relationship between height and lower leg length in modern Japanese for determining chair seat height

Abstract

One of the causes of poor posture in humans is the mismatch between chair height and body dimensions. Traditionally, body height and lower leg length have been used to determine the appropriate chair seat height. A previous study examining changes in the body proportions of modern Japanese adolescents using the chart method reported that the current proportions show an elongation of the torso (increase in sitting height and decrease in lower leg length) for both men and women. The purpose of this study was to determine the relationship between height and lower leg length in healthy adult subjects and provide basic data for determining chair seat height. The study included a total of 196 healthy adults (85 males and 111 females; mean age: 59.0 ± 14.2 years) living in Tokyo and its suburbs. Height was measured using a stadiometer, and lower leg length (height of the upper edge of the tibia) was measured using the Martin method with an anthropometer. Males showed a strong positive correlation (r = 0.795, p < 0.001) between height and tibia length. Females showed a moderate positive correlation (r = 0.664, p < 0.001) between height and tibia length. The positive correlation between height and lower leg length for both males and females suggest that these measurements can serve as criteria for selecting an appropriate chair for each individual.