You run with preternatural speed and endurance.

Prerequisite(s): Run.

Benefit: When running, you move seven times your normal speed if wearing medium, light, or no armor and carrying no more than a medium load, or six times your speed if wearing heavy armor or carrying a heavy load. When making a jump after a running start, you gain an additional bonus equal to your tier + 4 on your Acrobatics check.

You can run normally for a number of rounds equal to your Constitution score plus your tier, but after that you must succeed at Constitution checks to continue running.