Sportswear is the most diverse and fastest growing sector in the functional clothing market, which qualifies the athlete to compete to the highest level of performance. Sports textiles are considered one of the most important tech-textiles due to their direct influence on the performance rate and comfort of athletes and improving the sense of comfort. The research aims to produce Smart knitted fabrics that are compatible with warm-up operations before playing any sports to improve the attributes of current clothing using raw materials and building structures that serve the purpose of final use while wearing and using these fabrics. Experiments have been done to find the best samples implemented to produce fabrics suitable for sports warm-up clothing and to study the effect of treatments on the physical and mechanical properties of fabrics and where the quality is assessed for 16 samples treated with different PCMs materials, raw materials, and structural compositions. And it was found that the sample number (D4) implemented in the structural composition (1) Bamboo 70% - 30% cotton in the back and the face material Bamboo 70% - 30% cotton is the best for all functional properties of the fabrics produced under research using variables different study factors And by a quality factor of 84.7%, while the sample number (F2) executed in the structural composition (1) with a back of 100% cotton and the face material 75/35 polyester + viscose filaments 75/24 is the least at all concerning the functional properties of the fabrics produced under research using factors Different studies with a 75.4% quality factor. The researcher found that: treatment with phased change materials has accomplished the following: i) It reduced the air permeability of the fabrics, ii) It increased the water vapor permeability of the fabrics, iii) It increased the fabric's resistance to UV rays, iv) It increased the weight per square meter of fabrics, v) It reduced the thickness of the fabrics, vi) It reduced thermal insulation, and vii) It increased the bursting resistance of fabric.