scholarly journals Stable Coordination Variability in Overground Walking and Running at Preferred and Fixed Speeds

2021 ◽  
pp. 1-5
Author(s):  
Hannah E. Wyatt ◽  
Gillian Weir ◽  
Carl Jewell ◽  
Richard E.A. van Emmerik ◽  
Joseph Hamill

Coordination variability (CV) is commonly analyzed to understand dynamical qualities of human locomotion. The purpose of this study was to develop guidelines for the number of trials required to inform the calculation of a stable mean lower limb CV during overground locomotion. Three-dimensional lower limb kinematics were captured for 10 recreational runners performing 20 trials each of preferred and fixed speed walking and running. Stance phase CV was calculated for 9 segment and joint couplings using a modified vector coding technique. The number of trials required to achieve a CV mean within 10% of 20 strides average was determined for each coupling and individual. The statistical outputs of mode (walking vs running) and speed (preferred vs fixed) were compared when informed by differing numbers of trials. A minimum of 11 trials were required for stable mean stance phase CV. With fewer than 11 trials, CV was underestimated and led to an oversight of significant differences between mode and speed. Future overground locomotion CV research in healthy populations using a vector coding approach should use 11 trials as a standard minimum. Researchers should be aware of the notable consequences of an insufficient number of trials for overall study findings.

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Emma Reznick ◽  
Kyle R. Embry ◽  
Ross Neuman ◽  
Edgar Bolívar-Nieto ◽  
Nicholas P. Fey ◽  
...  

AbstractHuman locomotion involves continuously variable activities including walking, running, and stair climbing over a range of speeds and inclinations as well as sit-stand, walk-run, and walk-stairs transitions. Understanding the kinematics and kinetics of the lower limbs during continuously varying locomotion is fundamental to developing robotic prostheses and exoskeletons that assist in community ambulation. However, available datasets on human locomotion neglect transitions between activities and/or continuous variations in speed and inclination during these activities. This data paper reports a new dataset that includes the lower-limb kinematics and kinetics of ten able-bodied participants walking at multiple inclines (±0°; 5° and 10°) and speeds (0.8 m/s; 1 m/s; 1.2 m/s), running at multiple speeds (1.8 m/s; 2 m/s; 2.2 m/s and 2.4 m/s), walking and running with constant acceleration (±0.2; 0.5), and stair ascent/descent with multiple stair inclines (20°; 25°; 30° and 35°). This dataset also includes sit-stand transitions, walk-run transitions, and walk-stairs transitions. Data were recorded by a Vicon motion capture system and, for applicable tasks, a Bertec instrumented treadmill.


2021 ◽  
pp. 1-15
Author(s):  
Yuji Matsuda ◽  
Masaki Kaneko ◽  
Yoshihisa Sakurai ◽  
Keita Akashi ◽  
Sengoku Yasuo

2021 ◽  
pp. e20200051
Author(s):  
Yaron Haimovich ◽  
Oded Hershkovich ◽  
Sigal Portnoy ◽  
Isabella Schwartz ◽  
Raphael Lotan

Purpose: Our aim was to evaluate the Microsoft Kinect sensor (MKS) as a markerless system for motion capture and analysis of lower limb motion, compare it with a state-of-the-art marker-based system (MBS), and investigate its accuracy in simultaneously capturing several lower limb joint movements on several planes while participants walked freely. Method: Participants were asked to walk while gait data were simultaneously recorded by both the MKS and the MBS. Software for analysing the Kinect data stream was developed using Microsoft Visual Studio and Kinect for Windows software development kits. Visual three-dimensional (3D) C-Motion software was used to calculate 3D joint angles of the MBS. Deviation of the joint angles calculated by the two systems was calculated using root-mean-square error (RMSE) on the basis of a designated formula. Results: The calculated RMSE average was <5° between the two systems, a level of difference that has practically no clinical significance. Conclusions: Quantitative measurements of the joint angles of the knee and hip can be acquired using one MKS with some accuracy. The system can be advantageous for clinical use, at the pre- and post-treatment stages of rehabilitation, at significantly lower costs. Further evaluation of the MKS should be performed with larger study populations.


2020 ◽  
Vol 10 (24) ◽  
pp. 8818
Author(s):  
Aurélien Patoz ◽  
Thibault Lussiana ◽  
Adrien Thouvenot ◽  
Laurent Mourot ◽  
Cyrille Gindre

The aim was to identify the differences in lower limb kinematics used by high (DFhigh) and low (DFlow) duty factor (DF) runners, particularly their sagittal plane (hip, knee, and ankle) joint angles and pelvis and foot segment angles during stance. Fifty-nine runners were divided in two DF groups based on their mean DF measured across a range of speeds. Temporal characteristics and whole-body three-dimensional kinematics of the running step were recorded from treadmill runs at 8, 10, 12, 14, 16, and 18 km/h. Across speeds, DFhigh runners, which limit vertical displacement of the COM and promote forward propulsion, exhibited more lower limb flexion than DFlow during the ground contact time and were rearfoot strikers. On the contrary, DFlow runners used a more extended lower limb than DFhigh due to a stiffer leg and were midfoot and forefoot strikers. Therefore, two different lower limb kinematic mechanisms are involved in running and the one of an individual is reflected by the DF.


2017 ◽  
Vol 13 (4) ◽  
pp. 251-258 ◽  
Author(s):  
R. Graydon ◽  
D. Fewtrell ◽  
S. Atkins ◽  
J. Sinclair

Football (soccer) players have a high risk of injuring the lower extremities. To reduce the risk of ankle inversion injuries ankle braces can be worn. To reduce the risk of ankle contusion injuries ankle protectors can be utilised. However, athletes can only wear one of these devices at a time. The effects of ankle braces on stance limb kinematics has been extensively researched, however ankle protectors have had little attention. Therefore, the current study aimed to investigate the effects of ankle protectors on lower extremity kinematics during the stance phase of jogging and compare them with braced and uncovered ankles. Twelve male participants ran at 3.4 m/s in three test conditions; ankle braces (BRACE), ankle protectors (PROTECTOR) and with uncovered ankles (WITHOUT). Stance phase kinematics were collected using an eight-camera motion capture system. Kinematic data between conditions were analysed using one-way repeated measures ANOVA. The results showed that BRACE (absolute range of motion (ROM) = 10.72° and relative ROM = 10.26°) significantly (P<0.05) restricted the ankle in the coronal plane when compared to PROTECTOR (absolute ROM=13.44° and relative ROM =12.82°) and WITHOUT (absolute ROM=13.64° and relative ROM=13.10°). It was also found that both BRACE (peak dorsiflexion=17.02° and absolute ROM=38.34°) and PROTECTOR (peak dorsiflexion =18.46° and absolute ROM =40.15°) significantly (P<0.05) reduced sagittal plane motion when compared to WITHOUT (peak dorsiflexion =19.20° and absolute ROM =42.66°). Ankle protectors’ effects on lower limb kinematics closely resemble that of an unbraced ankle. Therefore, ankle protectors should only be used as a means to reduce risk of ankle contusion injuries and not implemented as a method to reduce the risk of ankle inversion injuries. Furthermore, the reductions found in sagittal plane motion of the ankle could possibly increase the bodies energy demand needed for locomotion when ankle protectors are utilised.


2009 ◽  
Vol 102 (1) ◽  
pp. 568-577 ◽  
Author(s):  
Andreanne Blanchette ◽  
Laurent J. Bouyer

Human locomotion results from interactions between feedforward (central commands from voluntary and automatic drive) and feedback (peripheral commands from sensory inputs) mechanisms. Recent studies have shown that locomotion can be adapted when an external force is applied to the lower limb. To better understand the neural control of this adaptation, the present study investigated gait modifications resulting from exposure to a position-dependent force field. Ten subjects walked on a treadmill before, during, and after exposure to a force field generated by elastic tubing that pulled the foot forward and up during swing. Lower limb kinematics and electromyographic (EMG) activity were recorded during each walking period. During force field exposure, peak foot velocity was initially increased by 38%. As subjects adapted, peak foot velocity gradually returned to baseline in ≤125 strides. In the adapted state, hamstring EMG activity started earlier (16% before toe off) and remained elevated throughout swing. After force field exposure, foot velocity was initially reduced by 22% and returned to baseline in 9–51 strides. Aftereffects in hamstring EMGs consisted of increased activity around toe off. Contrary to the adapted state, this increase was not maintained during the rest of swing. Together, these results suggest that while the neural control of human locomotion can adapt to force field exposure, the mechanisms underlying this adaptation may vary according to the timing in the gait cycle. Adapted hamstring EMG activity may rely more on feedforward mechanisms around toe off and more on feedback mechanisms during the rest of swing.


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