Saucony Progrid Trex Women's Cross Training Shoes. The Trex is a cross training shoe that bridges traditional underfoot training qualities with minimalism for the athlete wanting a lightweight shoe. This shoe will provide the support your foot needs while allowing it to move more naturally, exactly what you need for many gym activities. This shoe is built on the same last as the Kinvara, making it very responsive. So buy this Saucony Progrid Trex Women's Cross Training Shoes Was £74.99 Now £37.49.