The purpose of this study is to explore the dynamic change mechanism of clothing comfort perception during exercise, and deeply analyze the evolution characteristics of comfort perception of various body parts in different stages of exercise (warm-up, during exercise and relax after exercise). Through the test of 25 kinds of tight-fitting sportswear combinations. It is found that the influence of different clothing combinations on comfort perception presents regional differences, and the comfort change of the upper body is mainly reflected in the wet feeling and the hot feeling, while the lower body shows obvious sense of restraint; the wearing comfort of T2P1, T2P4, T3P5 and T4P3 are better than other combinations; with the extension of exercise time, the correlation of comfort of each part is gradually enhanced; the back, waist, chest and other body parts experience varying degrees of discomfort at rest, after exercise and during exercise; during exercise, the sense of restraint and stickiness of waist, hip, thigh and shank is particularly obvious. The research results fill the lack of research on the dynamic change of sportswear comfort, provide valuable design insights and promote the innovation of sportswear industry in terms of functionality and comfort. Through the in-depth analysis of the comfort change mechanism, this study provides theoretical support for the future development of sports medicine, sports psychology and smart sportswear, and helps the development of healthy sports and smart sportswear.