Laboratory assessment of range of motion and pressure associated with female soldiers wearing a ballistic vest

Abstract

Scope and Method of Study: The overall purpose of this research is to explore restrictions in performance and pressure exerted on the front torso of females wearing the InterceptorTM vests by measuring ROM and pressure-contact area. A three-phase study was conducted to meet the study objectives. Phase I examined military anthropometric database to determine age range, bust circumference range, and bust size groups for female soldiers in order to specify criteria for accepting subjects for the third phase. A focus group interview with female soldiers was the focus of Phase II in order to determine test garments and test movements to be used in the third phase to simulate female soldiers' typical movements and clothing. Phase III was a two-part laboratory experiment to determine ROM in subjects wearing and not wearing the ballistic vest while performing four selected movements. ROM was determined using the BTS Motion Capture System. Pressure-contact area was determined using Tekscan pressure sensors by subjects wearing the vest and performing the four movements. All volunteers were scanned using a 3D body scanner for selection as a subject and for placement into a bust size group.

Findings and Conclusions: Significant differences were found by vest for ROM for three of the four movements (shoulder flexion, shoulder horizontal adduction, and trunk flexion) with decreased ROM shown when subjects wore the vest. Examination of the ROM data for hip flexion with kneeling showed that the subjects used two ways of bending when performing this movement. A significant interaction effect was found for way of kneeling by bust size groups. For the bust size treatment, no significant differences were found for shoulder flexion, trunk flexion, and hip flexion with kneeling. A significant difference was found for shoulder horizontal adduction. Post hoc analysis found two significant groups with the large bust group having greater reduction in ROM as compared to the other bust groups. For pressure-contact area, significant bust size group differences occurred for shoulder and trunk flexion. However, post hoc analyses show conflicting results.