Carrying a weapon does not change stride-time variability during treadmill-based load carriage

Gait biomechanics during load carriage tasks are a focus of military research aiming to optimise performance and manage injury risk. However, the impact of weapon handling on gait during these tasks remains relatively unexplored. This study investigates non-linear stride time measures, specifically detrended fluctuation analysis (DFA) and sample entropy (SE), which assess the persistence and regularity of stride time. Seventeen Australian Army soldiers completed 12-minute walking trials on an instrumented treadmill, both with and without a replica rifle while carrying 23.2 kg of load at speeds of 3.5 km/h, 5.5 km/h, and 6.5 km/h. Heel contacts were tracked using an 18-camera Vicon system. Mixed-effect model analyses indicated that weapon handling did not significantly affect stride time variability (DFA p = 0.46) or regularity (SE p = 0.42), suggesting it may not be a critical factor in future studies of stride time variability during load carriage tasks.