Do Worn-In Tactical Boots Affect Lower-Extremity Biomechanics During Walking and Running?

Background: Much of the research conducted on tactical-style boots has evaluated the biomechanical effect of boots in brand-new condition; however, the extent to which changes due to wear influence lower-extremity biomechanics remains uninvestigated. The purpose of this study was to compare lower-extremity biomechanics with worn-in boots and running shoes during both walking and running. Methods: Lower-extremity biomechanical parameters were evaluated during walking and running in 12 individuals with previous tactical experience. Participants were asked to complete one 5 min bout of walking and running at a self-selected pace in both self-selected athletic shoes and their own worn-in standard-issue tactical boots while lower-extremity spatiotemporal, joint kinematic, kinetic, and ground reaction force data were collected. Differences between conditions were evaluated using the Wilcoxon signed-rank test. Results: Spatiotemporal measures of gait, as well as ankle and hip kinematics, were different between shoes and boots during walking. During running, no spatiotemporal differences existed. However, significant differences were found for the ankle, knee, and hip kinematics between shoe and boot conditions during both walking and running. Conclusions: The worn-in boots in our sample performed similarly to running shoes during both walking and running tasks. Though there were several biomechanical differences between boots and shoes during both tasks, small mean differences suggest that these differences may not be large enough to create substantive or relevant changes in performance. This information could aid in developing future tactical boot design strategies to help aid in lower-extremity injury as well as allowing for optimal performance when wearing boots.