Our original longsleeve for training in cold weather. Conquer the winter The Weather Shirt is designed for runners who don't want to depend on the temperature during training. The material plays an important role. The decisive difference, however, lies in the details. When training in the cold, comfort often remains outside. First you feel the cold; then it gets warm when you open something. The Weather Shirt is the solution. Pull the Performance-T underneath for additional performance. Temperature regulating fabric The special blend of polyester and lyocell makes the Weather Shirt soft, comfortable and warm. Nevertheless, it offers optimal protection in cold weather. The targeted air circulation allows moisture to drain away from the body more quickly, so you don't get cold.