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The purpose of this study was to evaluate the biomechanical performances, running stability of habitually barefoot (BR) and shod runners (SR) during barefoot jogging and running. Ten healthy male subjects, 5 habitually shod runners and 5 habitually barefoot runners, from two different ethnics participated in this study. Subjects performed jogging (2m/s) and running (4m/s) along a 10-m runway. Three-dimensional lower-limb kinematics, ground reaction force, center of pressure (COP) and contact time (CT), were collected during testing. During jogging and running, all participants adopted rear-foot strike pattern, SR had larger VALR. SR showed significantly larger lower-limb range of motion (ROM) in sagittal plane, significantly larger hip abduction and opposite knee ROM in frontal plane, as well as significantly larger ankle internal rotation in horizontal plane. All participants’ CT showed decreased trend with running speed up; and SR was significantly longer than BR; BR and SR in COP showed different trajectories, especially forefoot and rearfoot areas. Habitually barefoot and shod runner from different ethnics still exist significant differences in lower-extremity ROM; and different foot morphological of participants is an important influential factor for these variations.

The median frequency (MF) and mean power frequency (MPF) have been confirmed as reliable indicators of muscle fatigue during sustained contractions. The purpose of this study was to explore whether single-monitor arm could release muscle fatigue in neck-shoulder region while maintaining a prolonged seated posture viewing computer screen by measuring MF and MPF. Ten male healthy university students volunteered to participate in the test. Surface electromyography of splenius capitis (SC) and trapezius (TR) were recorded. Each subject performed normal text editing tasks or video watching activities for 120 minutes with different monitor arm positions (Fixed, moving downward and moving upward). Results showed that the MPF of SC and TR had significant decreased trend as monitor arm at fixed position. As monitor arm moving upward, the MF and MPF of both muscles decreased significantly with time and the MF showed the lowest decline rate during the entire testing process. No significant shift of MF and MPF were observed as monitor arm moving downward. Findings of this study may have important implications for people who use computer intensively to release neck-shoulder muscle fatigue.

The purpose of this study was to testing for difference in performance and injury risks between three different outsole configuration soccer boots on artificial turf. Fourteen experienced soccer players performed 45° cut test. They selected soccer boots with artificial ground design (AG), turf cleats boots (TF) and indoor boots (IN) randomly. A Vicon three dimension motion analysis system was used to capture kinematic data and Kistler force platform was used to record the ground reaction force. Novel Pedar-X insole plantar pressure measurement system was utilized to collect the plantar pressure synchronized. During 45° cut, artificial ground design (AG) showed significantly smaller peak knee flexion (p<0.001) and greater abduction angles (p<0.001) than indoor boots (IN). AG showed significantly greater vertical average loading rate (VALR) compared with TF (p=0.005) and IN (p=0.003). The results of plantar pressure found that AG showed the highest peak pressure and force-time integral in the heel (H) and medial forefoot (MFF). Artificial ground design (AG) and turf cleats (TF) may offer a performance benefit on artificial turf compared to IN. In summary, AG may enhance athletic performance on artificial turf, but also may undertake higher risks of non-contact injuries compared with TF and IN.