ACTIBREEZE is an advanced breathability technology developed to help runners keep cool and comfortable. The VENTILATE ACTIBREEZE SHORT SLEEVE top was engineered by our running apparel team for training in warmer conditions. This top's strategic body-mapped fabric provides advanced ventilation in key heat zones. Lightweight and quick-drying, it's also made with large slits on the sides that are functional for improving airflow and increasing freedom of movement.