Military training alters the fractal behavior of step width

Non-linear analyses have been successfully applied to gait with evidence that fractal behavior of gait-related variables provide insights into function. Specifically, shifts in the fractal behavior of step width from pink toward white noise reflects a loss of complexity and diminished adaptive capacity and functionality. We previously reported an apparent difference in the fractal behavior of step width during treadmill walking between Service members with transtibial amputations and able-bodied civilian. We now combine recently collected data and data from two previous studies to further explore the relationship between lower limb injury, military service, and step width fractal behavior. Service member, regardless of the presence or type of injury, demonstrate step width fractal behavior walked in a way that the fractal behavior of their gait was significantly closer to white noise (−0.5 dB/Hz²) than uninjured civilians (−0.82 dB/Hz²). This data suggests that military training/service leads to a change in step width fractal behavior. Further studies are needed to explore what may cause this difference and any implications this may have on stability or performance.