The clothing pressure with three types of stretch bottom were measured by ten female subjects in standing and walking positions. In order to clarify the factors affecting on the clothing pressure, the stress strain characteristics of the fabrics, 3D body shape of the subjects with bottoms, and the elongation of the skin due to posture change were examined. The results were: 1) the clothing pressure examined were in the range of comfort, 2) both of static and dynamic pressure increased with the extension stress of the fabric, 3) pressure fluctuations in walking showed various moving patterns due to fabrics, but the maximum value was observed at the patella in common, 4) the characteristics of skin elongation were divided into two types - a) shrinkage in one direction but elongation in other, and b) shrinkage in both directions - and 5) the clothing pressures estimated from the skin elongation were larger than the measured one, which suggested the slippage between the skin and the bottoms.
We conducted a survey on sportswear-caused skin friction that targeted 102 young women. Affected areas included the chest, groin, inner thigh, and armpit. Many of the respondents wore undergarments made of polyurethane material during exercise, and more than 60% wore tight-fitting undergarments. We then conducted a study by selecting 10 subjects. Using four samples with different composition and structure under two environmental conditions, we applied friction to the inner thigh and examined its effect on the three-dimensional microstructure of the skin's surface. The results showed that the coarseness parameter SRz, which represented the maximum value of the distance between the sulci cutis and crista cutis, was low under hot conditions, and the friction of knitted garments under hot conditions significantly lowered this value. It is thought that perspiring and softened skin became smooth as a result of the friction of slip-resistant knitted garments. The result suggested deserves attention when designing stretchable undergarments.