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Li-Xin Guo, Zhao-Wen Wang, Yi-Min Zhang, Kim-Kheng Lee, Ee-Chon Teo, He Li, and Bang-Chun Wen

The aim of this study is to investigate the effect of material property changes in the spinal components on the resonant frequency characteristics of the human spine. Several investigations have reported the material property sensitivity of human spine under static loading conditions, but less research has been devoted to the material property sensitivity of spinal biomechanical characteristics under a vibration environment. A detailed three-dimensional finite element model of the human spine, T12– pelvis, was built and used to predict the influence of material property variation on the resonant frequencies of the human spine. The simulation results reveal that material properties of spinal components have obvious influences on the dynamic characteristics of the spine. The annulus ground substance is the dominant component affecting the vertical resonant frequencies of the spine. The percentage change of the resonant frequency relative to the basic condition was more than 20% if Young’s modulus of disc annulus is less than 1.5 MPa. The vertical resonant frequency may also decrease if Poisson’s ratio of nucleus pulposus of intervertebral disc decreases.

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Owen Jeffries, Mark Waldron, Stephen D. Patterson, and Brook Galna

described in professional-level time trials conducted outdoors, 14 and low-frequency fluctuations in power output have been observed during indoor flat and simulated hilly conditions. 6 , 15 However, the magnitude of power variability between different environmental conditions and the differences in

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Thomas Dos’Santos, Paul A. Jones, Jonathan Kelly, John J. McMahon, Paul Comfort, and Christopher Thomas

athletes. 19 Variations in IMTP kinetics reported across the literature may be partially explained by methodological differences. 2 , 8 , 13 , 16 , 18 Early research used a sampling frequency of 500 Hz and 600 Hz, 8 , 13 whereas more recent investigations have implemented a sampling frequency of 1000 Hz

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Mu Qiao

questions remain for how each leg joint contributes to the spring of the entire body (ie, virtual leg). If the leg joints are all torsional springs and change stiffness proportionally, they will store and return the same percentage of mechanical energy independently of hopping frequency. Alternatively, leg

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Jesudas E. Menon, David J. Stensel, Keith Tolfrey, and Stephen F. Burns

by increasing meal frequency and decreasing absolute fat consumption at each meal. Such a strategy might suggest little capacity for exercise to further lower postprandial TAG. However, TAG clears slowly from the circulation and rarely returns to fasting concentrations between meals consumed across

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Ernst Albin Hansen

stride frequency and stride length . Gait & Posture, 18 ( 1 ), 69 – 77 . PubMed ID: 12855302 doi:10.1016/S0966-6362(03)00030-4 10.1016/S0966-6362(03)00030-4 De Luca , C.J. , & Erim , Z. ( 1994 ). Common drive of motor units in regulation of muscle force . Trends in Neurosciences, 17 ( 7

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Dong-Sung Choi, Hwang-Jae Lee, Yong-II Shin, Ahee Lee, Hee-Goo Kim, and Yun-Hee Kim

use of different vibration stimulation frequencies have not yet been investigated. This may give an insight how to select the vibration frequencies for specific purpose in treating the patients with neurologic diseases. Functional near-infrared spectroscopy (fNIRS) is a noninvasive optical technique

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Theodore Kent Kessinger, Bridget Melton, Theresa Miyashita, and Greg Ryan

Clinical Scenario Resistance training (RT) is a common and well-accepted method for the development of muscular strength, power, and hypertrophy. Numerous studies have been undertaken to provide insight into the differences between the frequency of training, 1 – 6 number of muscle groups exercised

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Stefan Sebastian Tomescu, Ryan Bakker, Tyson A.C. Beach, and Naveen Chandrashekar

muscle forces. The raw marker and force platform data contain high-frequency noise that may require low-pass filtering to remove. A low-pass filter is designed to attenuate noise above its cutoff frequency and leave the true signal relatively unaffected. Selecting the correct cutoff frequency is a

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Gianluca Vernillo, Adrien Mater, Gregory Doucende, Johan Cassirame, and Laurent Mourot

Our concern in this study was with the consequences of a fatiguing ultratrail on self-optimizing capability during uphill and downhill (DR) running. We showed that similar dynamics of stride frequency (SF) adjustments occurred as those found in a nonfatigued state after a 6-hour run. 1 This