The Effects of Various Military Issued Footwear on Impact Loading During Running

Open Access
- Author:
- Hoopert, Courtney Marie
- Area of Honors:
- Kinesiology
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Allison Altman Singles, Thesis Supervisor
Dr. Sandy Feinstein, Thesis Honors Advisor - Keywords:
- combat boots
ground reaction force
impact loading - Abstract:
- Military members have a high musculoskeletal injury rate, which limits physical participation. These injuries are due to overuse and may be caused by repeated impact loading to the lower extremities. These issues usually start in boot camp and occur more often in women. The purpose of this study was to assess the impact-related injury risk of three types of military footwear during running. It was expected that impact loading would be higher in the stiff boots compared to the running sneakers. Ground reaction forces were collected for 15 female test subjects in their personal running shoes and two different military issued combat boots. The impact peak (IPz), average loading rate (ALRz), instantaneous loading rate (ILRz), and peak force (Peakz) were extracted from the vertical ground reaction force and compared among the three types of footwear using one-way repeated measures ANOVA. Instantaneous load rate for the sneaker was 25.5% greater than the Belleville (Bell) boot and 34.5% greater than the OCP tactical (OCP) boot. Average load rate for the sneaker was 51.8% greater than the Bell boot and the Bell boot was 48.0% greater than the OCP Boot. The sneaker was 29.0% more comfortable compared to the OCP boot and 64.3% more comfortable compared to the Bell boot. Impact peak and peak force were not different between the footwear conditions. This data shows, contrary to the hypothesis, that impact is absorbed better in combat boots compared to sneakers because of the sole thickness. These findings do match previous studies, that there was an inverse change between impact loading and hardness of the sole. The data suggests that high impact loading in combat boots does not contribute to high rates of injury in military service members. The high rate of injury may be explained by other factors such as the muscular demand due to the weight of the boot, kinematic factors, or training factors.