Ready to rock on race day? The Pearl Izumi isoTransition lets you shift right into high gear when you really need it. This running shoe was dreamt up by Tim DeBoom, the two-time IronMan World Champion. With a breathable seamless upper, the isoTransition has excellent out-of-the-box comfort, and its seam-free interior keeps hotspots at bay. Its quick-pull lacing system makes it easy to pull on and go. The drainage system in the midsole doesn’t let anything weigh you down, and sweat and water can easily escape. With a weight of 7.5 ounces, the isoTransition is one of the lightest shoes in the Pearl Izumi collection.