Footwear has a modifying effect on tibial loading during military weight carriage

Abstract

Abstract This study investigated how different footwear conditions influence tibial loading across incremental load carriage during walking. Ten military-trained male participants completed walking trials under three weight conditions (0, 15, and 30 kg) and three footwear conditions (barefoot, trainers, and military boots) at 1.67 m/s. Kinematic (120 Hz) and kinetic (1200 Hz) data were collected using motion capture and force plates. Tibial loading was estimated via musculoskeletal modeling and beam theory, focusing on peak tibial bending moments and cumulative-weighted tibial impulse. A two-way repeated measures ANOVA ( $$p < 0.05$$ ) examined main effects and interactions of load and footwear. Post hoc pairwise comparisons with Bonferroni corrections ( $$p_{\text {corr}} < 0.05$$ ) identified significant differences. A significant interaction effect was observed for peak tibial bending moments and cumulative-weighted tibial impulse per kilometer ( $$p < 0.05$$ ). In trainers, tibial loading increased progressively across all loads (0 kg < 15 kg < 30 kg, all $$p_{\text {corr}} < 0.05$$ ). In military boots, loading increased from 0 to 15 kg ( $$p_{\text {corr}} < 0.05$$ ) but not between 15 and 30 kg. Weight carriage increased tibial loading, but footwear modified this relationship. Military boots showed no significant change between 15 and 30 kg. These findings suggest implications for tibial stress injury, though further research is needed.