First Strike - Spartan Speed 4

John tensed and ran. It took him three strides to build to his top-speed sprint. His adrenaline spiked and it made his blood burn. He felt time slow, his perception running at an overclocked pace. He focused on speed—putting one foot in front of the other. His boots dug into cobblestones, crushed rock, and sent a fine spray of gravel behind him. He saw three obstacles in his path: a group of startled Grunts. He slammed the butt of his rifle into the nearest one, and crushed its skull. The dead Grunt spun end over end and landed in a heap. He heard squawks and shouts around him but didn't stop to look.

- Halo: First Strike, Chapter 33