Abstract: Shrinkage design is the key factor affecting the fit and comfort of shaping pants. Reasonably designed shrinkage rate of shaping pants can modify the curve of the body while maintaining comfort. By observing the fatigue changes of abdominal muscles, rectus femoris, erector spine, gluteus maximus and hamstring muscles at different shrinkage rates through surface EMG test, this paper obtained the corresponding fabric shrinkage rate range when the muscle fatigue increases and decreases. Based on the expected adjustment trend and range of muscle fatigue, the paper selected the appropriate shrinkage rate for each area, so as to obtain the design scheme of shrinkage rate of shaping pants. This design method of shaping pants shrinkage rate based on directional adjustment of muscle fatigue not only takes into account the pressure comfort of clothing but also considers the adjustment effect of pressure on muscle fatigue. By helping to balance muscle strength, slowing down the process of muscle fatigue, the new design can improve the wearing comfort of body shaping pants, and provide a method reference for the shrinkage rate configuration of body shaping pants.