Weapon handling during load carriage does not affect lower-limb coupling variability in military personnel

This exploratory study aimed to examine the effect of weapon handling on lower-limb coupling variability of military personnel during load carriage. Seventeen soldiers (12 males, 5 females) completed two 12-min bouts of walking at 5.5 km⋅hr^-1 on an instrumented treadmill carrying 23 kg of external load. The two trials were completed either with or without handling a weapon. To quantify coupling variability, continuous relative phase standard deviation was calculated for nine couplings across combinations of four segments (pelvis, thigh, shank, and foot) and three planes (sagittal, frontal, and transverse). Weapon handling did not significantly affect the variability of any coupling. Any effect of weapon handling on coupling variability may occur elsewhere such as in the torso. Therefore, research quantifying lower-limb coupling variability in military personnel may be undertaken, irrespective of incorporating weapon handling.