Background: Height is an important factor in determining a person’s appearance, so people often wear height increase elevator shoes insoles (HIESI) or high heels to make themselves look taller. However, high heels often act as a risk factor for musculoskeletal diseases. Objectives: To investigated how muscle tone and muscle stiffness in the lumbar region of young adult men varied according to the height of the HIESI, and analyzed the correlation. Design: Non-randomised trial. Methods: Muscle tone and muscle stiffness in the upper and lower lumbar regions of 20 healthy young adult men in an upright standing position were measured as the subjects wore no insoles and 2 cm, 3 cm, and 4 cm insoles. Results: Muscle tone and muscle stiffness in the lumbar region did not show a significant change according to the increased height of the HIESI. However, a positive correlation was observed when the subjects wore 4 cm HIESI, as there was a significant increase (P<.05) in muscle tone and stiffness in the left side of the upper lumbar region and in the right side of the lower lumbar region. Conclusion: Wearing HIESI for short periods of time in the static standing position did not cause a change in muscle tone and muscle stiffness in the lumbar region. However, wearing 4 cm HIESI demonstrated a correlation of increased muscle tone and stiffness in the upper and lower lumbar regions in an asymmetric manner.

The present study analyzed data from the 3D measurement of the feet of men aged over 20 years residing in the capital region as part of the 6th Anthropometry of Size Korea. To analyze the characteristics of the foot shapes of young men aged 20~39 years and middle-aged/elderly men aged 40~69 years by age and by type, a cluster analysis was conducted using the factors derived through the factor analysis as independent variables. The results of the study that analyzed the characteristics of foot shapes by type according to differences in age were as follows. First, through the analysis of the characteristics of the foot shapes of young men by type, five factors were extracted, and the foot shapes were classified into three types: Type 1 (short and flat), Type 2 (thick), and Type 3 (long and wide). Second, through the analysis of the characteristics of the foot shapes of middle-aged/elderly men by type, six factors were extracted, and the foot shapes were classified into four types: Type 1 (short and regular), Type 2 (flat), Type 3 (thick), and Type 4 (long and regular). The results of the present study are expected to serve as basic data for the design of shoes by age and foot type.

The purpose of this study is to provide foot classification on young men and women by factor analysis. The sample for this work was chosen from data which were collected and measured by Size Korea during two years (2003~2004). In order to analyze and compare features of the foot of young men and women, analysis was performed about 911 subjects (male: 467, female: 444) on 24 parts such as height (8 parts), width (5 parts), thickness (1 part), circumference (3 parts), length (3 parts) and angle (4 parts). The result of this study can be applied in manufacturing and design of shoes and socks. Also, it will enable us to have fruitful information on considerable items during manufacturing and design of shoes and socks.