Although it seems obvious that texting while walking would affect your walking by making you less aware of your surroundings, it also has significant changes on your gait. These changes can make it more likely that the texter will fall:
Most noticeable, the volunteers began to walk with a more upright and rigid body position. Their heads froze into cocked and largely unchanging positions, eyes on the screen, chins bent toward their chests. Their necks and lower back joints had significantly less range of motion. They displayed “tighter mechanical constraint” in their upper bodies and midsections, according to the researchers; arms stopped swinging loosely and were bent and locked into place. The pelvic joints likewise stiffened, making leg motion jerkier. In general, the texters moved “like robots,” said Siobhan Schabrun, an honorary senior fellow at the University of Queensland, who led the study.
Simultaneously, their gait patterns changed. Texters took significantly shorter steps, and their pace slowed. They also “deviated more from a straight line,” the study’s authors wrote, meaning that with almost every step, they set their feet farther to the side.