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Locomotion

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A Comparison of Both Motorized and Nonmotorized Treadmill Gait Kinematics to Overground Locomotion

Adam M. Fullenkamp, Danilo V. Tolusso, C. Matthew Laurent, Brian M. Campbell, and Andrea E. Cripps

The use of traditional motorized treadmills (MTs) is an established approach for physiological conditioning, sport-specific training, gait retraining, and the study of human locomotion. In particular, MTs offer the convenience of spatial control, enabling locomotion in an environment that is

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Variation of Age-Related Changes in Endurance Performance Between Modes of Locomotion in Men: An Analysis of Master World Records

Romuald Lepers, Paul J. Stapley, and Thomas Cattagni

mode of locomotion influences the age-related changes in physical performance. It is interesting that these studies revealed that the decline in cycling was less pronounced than in swimming or running. 9 – 11 Several hypotheses have been proposed to explain the smaller decline in cycling performance

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The Applicability of Thigh-Worn vs. Hip-Worn ActiGraph Accelerometers During Walking and Running

Katja Krustrup Pedersen, Esben Lykke Skovgaard, Ryan Larsen, Mikkel Stengaard, Søren Sørensen, and Kristian Overgaard

). Statistical Analysis All data are expressed as means ( M ) ± standard error of the mean (SEM). Linear regression analyses were performed between VM cpm and speed of locomotion, and between VM cpm and oxygen consumption (separate analyses between walking and running). Fisher’s r-to-z transformation was used to

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Cycle Rate, Length, and Speed of Progression in Human Locomotion

James G. Hay

There have been few attempts to synthesize the knowledge gleaned from the study of cyclic human locomotion and, specifically, to determine whether there are general laws that describe or govern all such forms of locomotion. The purpose of this paper was to test the hypothesis that, when a human participant performs multiple trials of a given form of cyclic locomotion at a wide range of speeds (S) and without constraint on cycle rate (CR) or cycle length (CL), the relationships of CR vs. S and CL vs. S have the same basic characteristics as do those for any other form of cyclic locomotion. Data were gathered from published and unpublished sources. For each participant and form of locomotion, CR-vs.-S and CL-vs.-S relationships were plotted on a common scattergram with S on the abscissa and both CR and CL on the ordinate. Analysis of data collected on 49 participants and 12 forms of locomotion showed that, for every combination of participant and form of locomotion considered (excluding combinations involving simulated locomotion), the relationships of CR vs. S and CL vs. S had the same basic characteristics. These relationships were quadratic in form with CR-vs.-S concave upward and CL-vs.-S concave downward. The factor that made the greater contribution to increases in S was a function of S, with CL the primary factor at low S and CR the primary factor at high S. In short, the results obtained provided unequivocal support for the hypothesis of the study. The basic CR-vs.-S and CL-vs.-S relationships observed for forms of actual locomotion were also observed for some, but not all, of the forms of simulated locomotion examined.

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Characterization of a System for Studying Human Gait during Slope Walking

Andrea N. Lay, Chris J. Hass, D. Webb Smith, and Robert J. Gregor

Sloped walking surfaces provide a unique environment for examining the bio-mechanics and neural control of locomotion. While sloped surfaces have been used in a variety of studies in recent years, the current literature provides little if any discussion of the integrity, i.e., validity, of the systems used to collect data. The goal of this study was to develop and characterize a testing system capable of evaluating the kinetics of human locomotion on sloped surfaces. A ramped walkway system with an embedded force plate was constructed and stabilized. Center of pressure and reaction force data from the force plate were evaluated at 6 ramp grades (0, 5, 15, 25, 35, and 39%). Ground reaction force data at 0% grade were effectively the same as data from the same force plate when mounted in the ground and were well within the range of intrasubject variability. Collectively, data from all tests demonstrate the fidelity of this ramp system and suggest it can be used to evaluate human locomotion over a range of slope intensities.

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Normative Extensor Hallucis Brevis Muscle Activity During Locomotion Following the Development of a Novel Ultrasound-Guided Fine-Wire Electromyography Protocol

Kelly A. Robb, Keara Sutherland, and Stephen D. Perry

) define an ultrasound-guided fine-wire EMG protocol to record EHB muscle activity during locomotion and (2) report normative EMG profiles of healthy young adults during locomotion, serving as benchmark data for future experimental research. Until recently, our understanding of the human foot has been

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Varying Treadmill Speed and Inclination Affects Spontaneous Synchronization When Two Individuals Walk Side by Side

Jeff A. Nessler, Gerald Kephart, Jason Cowell, and Charles J. De Leone

Studying spontaneous synchronization of stepping as two individuals walk on side-by-side treadmills may be useful for understanding the control of bipedal locomotion and may have implications for gait rehabilitation. Existing data suggest that this behavior is related to differences in leg length, walkway slope, and overground speed between partners, and might be promoted by altering these variables. This idea was evaluated here as 24 pairs of subjects stepped on side-by-side treadmills under several conditions of relative speed and slope. Overall, pairings that demonstrated very little spontaneous synchronization with the same treadmill speed and slope exhibited significant increases in this behavior when one treadmill was manipulated. Conversely, pairings that demonstrated a tendency to synchronize under normal conditions exhibited significant decreases in this behavior when either treadmill was altered.

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A Nonlinear Dynamics Approach to Human Movement

Richard E.A. Van Emmerik, Michael T. Rosenstein, William J. McDermott, and Joseph Hamill

Nonlinear dynamics and dynamical systems approaches and methodologies are increasingly being implemented in biomechanics and human movement research. Based on the early insights of Nicolai Bernstein (1967), a significantly different outlook on the movement control “problem” over the last few decades has emerged. From a focus on relatively simple movements has arisen a research focus with the primary goal to study movement in context, allowing the complexity of patterns to emerge. The approach taken is that the control of multiple degrees-of-freedom systems is not necessarily more difficult or complex than that of systems only comprising a few degrees of freedom. Complex patterns and dynamics might not require complex control structures. In this paper we present a tutorial overview of the mathematical underpinnings of nonlinear dynamics and some of its basic analysis tools. This should provide the reader with a basic level of understanding about the mathematical principles and concepts underlying pattern stability and change. This will be followed by an overview of dynamical systems approaches in the study of human movement. Finally, we discuss recent progress in the application of nonlinear dynamical techniques to the study of human locomotion, with particular focus on relative phase techniques for the assessment of coordination.

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Ground Reaction Forces during Human Locomotion on Railroad Ballast

Chip Wade and Mark S. Redfern

Locomotion over ballast surfaces provides a unique situation for investigating the biomechanics of gait. Although much research has focused on level and sloped walking on a smooth, firm surface in order to understand the common kinematic and kinetic variables associated with human locomotion, the literature currently provides few if any discussions regarding the dynamics of locomotion on surfaces that are either rocky or uneven. The purpose of this study was to investigate a method for using force plates to measure the ground reaction forces (GRFs) during gait on ballast. Ballast is a construction aggregate of unsymmetrical rock used in industry for the purpose of forming track bed on which railway ties are laid or in yards where railroad cars are stored. It is used to facilitate the drainage of water and to create even running surfaces. To construct the experimental ballast surfaces, 31.75-mm (1¼-in.) marble ballast at depths of approximately 63.5 mm (2.5 in.) or 101.6 mm (4 in.) were spread over a carpeted vinyl tile walkway specially designed for gait studies. GRF magnitudes and time histories from a force plate were collected under normal smooth surface and under both ballast surface conditions for five subjects. GRF magnitudes and time histories during smooth surface walking were similar to GRF magnitudes and time histories from the two ballast surface conditions. The data presented here demonstrate the feasibility of using a force plate system to expand the scope of biomechanical analyses of locomotion on ballast surfaces.