All

subjects were advised to report occurrence of running pain and injury. The Institutional Review Board of the University of Cincinnati approved the study, and all participants gave written consent. Running kinematics were captured for each subject on a standard treadmill (Smooth Fitness 76HRPRO, King of Prussia, PA, USA) using an eight-camera Vicon MX T10 3D motion capture system (Vicon Nexus, Centennial, CO, USA) at 120 fps and a Basler Pilot pia640 monochrome high-speed digital camera (Balser AG, Ahrensburg, Germany). RGFP966 price Video recording occurred at 200 fps with the lens set perpendicular to the long axis of the treadmill at distance of 1.0 m and 0.5 m above the lab floor. All trials were of 10-s duration following a brief period of treadmill acclimation: two quiet stance trials (recorded before and after gait trials), two walking trials at 1.25 m/s and three at 1.75 m/s, and self-determined running speeds for seven trials at half

of race pace and seven at half marathon race pace. During the initial baseline session, all participants wore standard running shoes. Subsequently, the experimental group began transitioning to minimal footwear. For the concluding Ceritinib cell line post-treatment session, the control group ran in standard shoes and experimental group in minimal footwear. The foot strike event was identified visually (by EEM) on synchronized high-speed digital video and 2D Vicon reconstruction run at 1/8th speed. Video based L-NAME HCl foot contact was assessed relative to the treadmill deck. Vicon 2D contact was then identified by first foot marker deceleration to zero, either the heel or metatarsal head marker. Vicon frame numbers associated with foot contact were recorded and later processed with custom MATLAB (Math Works Inc., Natick, MA, USA) scripts filtered through a 4th order zero-lag low-pass Butterworth filter with a cut-off frequency of 10 Hz. Following Lieberman et al.,21 we calculated the right foot angle of incidence

(AOI) at foot strike as the angle between the foot segment defined by 14-mm markers overlying the left lateral malleolus and the fifth metatarsal head (LMT5), and a global horizontal through the LMT5. The running AOI was standardized to the angle obtained in quiet stance (Table 2). We identified foot strike type by AOI as an angle greater than 0° indicating forefoot contact (FFS), less than 0° heel strike (RFS), and an angle equal to 0° indicating midfoot contact (MFS)21 (Table 2). Because there is no direct method to measure force production of the ABH, FDB, and ADM, we used muscle CSA and MV to assess strength of the intrinsic muscles based on correlations between maximal force production and muscle area and volume.24, 25, 26, 27, 28 and 29 In order to quantify CSA and MV, we performed same-day MRI scans matched to the kinematic session schedule. Five 1.