Women's athletic jersey Reebok Activchill : Being hot makes any workout harder. This women's Reebok workout shirt is designed with the ACTIVCHILL cooling system to help you handle HIIT classes and sprints on the bike. The breathable fabric is cool to the touch so you can focus on the essentials. [REE]CYCLED: Made with at least 30% recycled or reused materials; zero virgin polyester.