Key Features & Technology These performance tops typically incorporate several technical features to manage heat during intense sessions: ACTIVCHILL Fabric: Engineered with enhanced breathability to help regulate body temperature and keep you cool. Speedwick Technology: Wicks sweat away from the body to ensure you stay dry throughout your workout. Design for Motion: Often features a racerback or swimmer's back design to allow a full range of motion for overhead lifts and athletic movements. Support: Many versions include a built-in shelf bra for light to medium support during training.