scholarly journals Postural changes and their effects in elite riders when actively influencing the horse versus sitting passively at trot

2016 ◽  
Vol 12 (1) ◽  
pp. 27-33 ◽  
Author(s):  
M.T. Engell ◽  
H.M. Clayton ◽  
A. Egenvall ◽  
M.A. Weishaupt ◽  
L. Roepstorff

The objectives were to compare sagittal plane posture of the pelvis, trunk and head of elite dressage riders when they ride actively to train the horse versus sitting passively and following the horses’ movements at trot, and to evaluate the effects of these changes in rider posture on load distribution on the horse’s back. Synchronised motion capture and saddle mat data of seven elite dressage riders were used to measure minimal and maximal angles and range of motion (ROM) for the pelvic, trunk and head segments, the angle between pelvis and trunk segments, phase-shift between pitching motions of pelvis and trunk, and pelvic translation relative to the saddle. Non-parametric statistical tests compared variables between the two rider postures. In the passive rider posture the pelvis, trunk and head showed two pitching cycles per stride. Maximal posterior and anterior pelvic rotation occurred, respectively, early and late in the horse’s diagonal stance phase. Compared with pelvic movements, trunk movements were slightly delayed and head movements were out-of-phase. In the active rider posture the pelvis and trunk pitched further posteriorly throughout the stride. Most of the riders showed similar sagittal plane movements of the axial body segments but with some notable individual variations.

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3277
Author(s):  
Juan Luis Florenciano Restoy ◽  
Jordi Solé-Casals ◽  
Xantal Borràs-Boix

The objectives of this study were to determine the amplitude of movement differences and asymmetries between feet during the stance phase and to evaluate the effects of foot orthoses (FOs) on foot kinematics in the stance phase during running. In total, 40 males were recruited (age: 43.0 ± 13.8 years, weight: 72.0 ± 5.5 kg, height: 175.5 ± 7.0 cm). Participants ran on a running treadmill at 2.5 m/s using their own footwear, with and without the FOs. Two inertial sensors fixed on the instep of each of the participant’s footwear were used. Amplitude of movement along each axis, contact time and number of steps were considered in the analysis. The results indicate that the movement in the sagittal plane is symmetric, but that it is not in the frontal and transverse planes. The right foot displayed more degrees of movement amplitude than the left foot although these differences are only significant in the abduction case. When FOs are used, a decrease in amplitude of movement in the three axes is observed, except for the dorsi-plantar flexion in the left foot and both feet combined. The contact time and the total step time show a significant increase when FOs are used, but the number of steps is not altered, suggesting that FOs do not interfere in running technique. The reduction in the amplitude of movement would indicate that FOs could be used as a preventive tool. The FOs do not influence the asymmetry of the amplitude of movement observed between feet, and this risk factor is maintained. IMU devices are useful tools to detect risk factors related to running injuries. With its use, even more personalized FOs could be manufactured.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Takumi Mieda ◽  
Masahiro Kokubu

AbstractIn blind football, players predict the sound location of a ball to underpin the success of ball trapping. It is currently unknown whether blind footballers use head movements as a strategy for trapping a moving ball. This study investigated characteristics of head rotations in blind footballers during ball trapping compared to sighted nonathletes. Participants performed trapping an approaching ball using their right foot. Head and trunk rotation angles in the sagittal plane, and head rotation angles in the horizontal plane were measured during ball trapping. The blind footballers showed a larger downward head rotation angle, as well as higher performance at the time of ball trapping than did the sighted nonathletes. However, no significant differences between the groups were found with regards to the horizontal head rotation angle and the downward trunk rotation angle. The blind footballers consistently showed a larger relative angle of downward head rotation from an early time point after ball launching to the moment of ball trapping. These results suggest that blind footballers couple downward head rotation with the movement of an approaching ball, to ensure that the ball is kept in a consistent egocentric direction relative to the head throughout ball trapping.


Author(s):  
Elizabeta Ramova ◽  
Leonid Ramov

Abstract Introduction: In the new millennium, the medical community still deals with the treatment of idiopathic scoliosis as a three-dimensional (3D) curvature known in India before Hippocrates. However, we doctors that deal with deformities of the spine, stick to Reichalt's rule for treatment according to the size of the curvature and its progression. The aim of our study is to explain our own opinion for progression of bad posture in school children according to physical inactivity and use of video terminals (VT). Materials and methods: We have made some researches about standards of school screening for bad posture and its impact on morphological and functional changes in them. Results: Most of school children spend more than 2 hours in front of video terminals, they have increased body weight, and postural changes in sagittal plane. Discussion: Some postural bad positions in age of intensive growth can became structural. In the era of fast technology development the future generation shall have functional changes on body like result of long standing in bad position. Conclusion: The future studies for bad posture in school children should be aimed to find how much long sitting in front of VT can affect their health in the adult age.


2008 ◽  
Vol 32 (1) ◽  
pp. 111-126 ◽  
Author(s):  
Lexyne L. McNealy ◽  
Steven A. Gard

In able-bodied individuals, the ankle joint functions to provide shock absorption, aid in foot clearance during the swing phase, and provides a rocker mechanism during stance phase to facilitate forward progression of the body. Prosthetic ankles currently used by persons with lower limb amputations provide considerably less function than their anatomical counterparts. However, increased ankle motion in the sagittal plane may improve the gait of persons with lower limb amputations while providing a more versatile prosthesis. The primary aim of this study was to examine and quantify temporal-spatial, kinematic, and kinetic changes in the gait of four male subjects with bilateral trans-femoral amputations who walked with and without prosthetic ankle units. Two prosthesis configurations were examined: (i) Baseline with only two Seattle LightFoot2 prosthetic feet, and (ii) with the addition of Endolite Multiflex Ankle units. Data from the gait analyses were compared between prosthetic configurations and with a control group of able-bodied subjects. The amputee subjects' freely-selected walking speeds, 0.74 ± 0.19 m/s for the Baseline condition and 0.81 ± 0.15 m/s with the ankle units, were much less than that of the control subjects (1.35 ± 0.10 m/s). The amputee subjects demonstrated no difference in walking speed, step length, cadence, or ankle, knee, and hip joint moments and powers between the two prosthesis configurations. Sagittal plane ankle range of motion, however, increased by 3–8° with the addition of the prosthetic ankle units. Compared to the control group, following initial contact the amputee subjects passively increased the rate of energy storage or dissipation at the prosthetic ankle joint, actively increased the power generation at the hip, and increased the extension moment at the hip while wearing the prosthetic ankle configuration. The amputee subjects increased the power generation at their hips, possibly as compensation for the reduced rate of energy return at their prosthetic ankles. Results from subject questionnaires administered following the gait analyses revealed that the prosthetic ankle units provided more comfort during gait and did not increase the perceived effort to walk. The subjects also indicated that they preferred walking with the prosthetic ankle units compared to the Baseline configuration. The results of the study showed that the prosthetic ankle units improved sagittal plane ankle range of motion and increased the comfort and functionality of the amputee subjects’ prostheses by restoring a significant portion of the ankle rocker mechanism during stance phase. Therefore, prosthetic ankle mechanisms should be considered a worthwhile option when prostheses are prescribed for persons with trans-femoral amputations.


2016 ◽  
Vol 45 ◽  
pp. 90-96 ◽  
Author(s):  
Kimberly D. Dahl ◽  
He Wang ◽  
Jennifer K. Popp ◽  
D. Clark Dickin

2014 ◽  
Vol 104 (2) ◽  
pp. 183-190 ◽  
Author(s):  
Renan A. Resende ◽  
Sérgio T. Fonseca ◽  
Paula L. Silva ◽  
Antônio E. Pertence ◽  
Renata N. Kirkwood

Background The forefoot midsole stiffness of the shoe may affect the kinematics of the foot segments. We evaluated the effects of two different levels of forefoot midsole stiffness on the angular displacement of the forefoot and rearfoot in the three planes of motion during the stance phase of gait. Methods Thirty-six participants walked on a 10-m walkway at their self-selected speed wearing shoes having either low or high forefoot midsole stiffness. Three-dimensional kinematic data of the foot segments were obtained during the stance phase of gait using an eight-camera motion analysis system synchronized with a force platform. The dependent variables were forefoot and rearfoot total range of motion and maximum and minimum angle values in the sagittal, frontal, and transverse planes of motion. Results Reduced forefoot midsole stiffness produced significantly greater forefoot total range of motion in the sagittal plane (1.59°). The low-stiffness condition also increased the magnitude of the forefoot dorsiflexion angles (4.14°). Furthermore, the low-stiffness condition increased the magnitude of the rearfoot inversion (1.21°) and adduction (11.38°) angles and reduced the rearfoot abduction angle (12.1°). Conclusions It is likely that reduced stiffness of the forefoot midsole stretched the plantar fascia, increasing rearfoot stability during the stance phase of gait. Increased muscular contraction may also explain increases in rearfoot stability. Therefore, the integrity of the plantar fascia and ankle muscles' force and resistance should be considered when choosing a shoe with reduced or increased forefoot midsole stiffness for walking.


2018 ◽  
Vol 11 (21) ◽  
pp. 22-27
Author(s):  
Nicolae-Adrian Jurjiu ◽  
Corina Pantea

Abstract The aim of this paper was to study a number of 34 athletes practicing different kinds of sports activities, in order to determine whether they have developed a certain spine deficiency and if there is any association between the type of sports they practice and the postural changes they develop. Methods: In this study we have enrolled 12 members of the men’s volleyball team of the “West University of Timisoara”, 9 members of the men’s football team ASU Politehnica Timișoara, and 13 members of the men’s basketball team BC SCM Timișoara. Postural analysis was carried out with the Zebris CMS-10 from the mechatronics department of the Politehinca University Timisoara, a device that determines the spatial coordinates of the spinous processes. From the obtained data we have established the angle of the spinal deviation both sagittal and frontal, in a similar manner as with the Cobb method. Results: We have observed a reduction in the spinal curvature in volleyball players; 8 out of 12 had values under the normal range that can in time lead to a rigid spine. 7 players from the basketball team presented values out of the normal range for kyphosis and 8 of them for lordosis, while all except two of the team players present with a front plane deviation of the spine. From the evaluation of the football players from ASU Politehnica Timișoara we cannot generalize a deviation in the sagittal plane, but all of them present deviations in the frontal plane. Conclusion: Professional athletes can also present postural changes determined by the positions they most frequently adopt depending on the type of sports they practice.


2021 ◽  
Author(s):  
Md Sanzid Bin Hossain ◽  
Joseph Drantez ◽  
Hwan Choi ◽  
Zhishan Guo

<div>Measurement of human body movement is an essential step in biomechanical analysis. The current standard for human motion capture systems uses infrared cameras to track reflective markers placed on the subject. While these systems can accurately track joint kinematics, the analyses are spatially limited to the lab environment. Though Inertial Measurement Unit (IMU) can eliminate the spatial limitations of the motion capture system, those systems are impractical for use in daily living due to the need for many sensors, typically one per body segment. Due to the need for practical and accurate estimation of joint kinematics, this study implements a reduced number of IMU sensors and employs machine learning algorithm to map sensor data to joint angles. Our developed algorithm estimates hip, knee, and ankle angles in the sagittal plane using two shoe-mounted IMU sensors in different practical walking conditions: treadmill, level overground, stair, and slope conditions. Specifically, we proposed five deep learning networks that use combinations of Convolutional Neural Networks (CNN) and Gated Recurrent Unit (GRU) based Recurrent Neural Networks (RNN) as base learners for our framework. Using those five baseline models, we proposed a novel framework, DeepBBWAE-Net, that implements ensemble techniques such as bagging, boosting, and weighted averaging to improve kinematic predictions. DeepBBWAE-Net predicts joint kinematics for the three joint angles under all the walking conditions with a Root Mean Square Error (RMSE) 6.93-29.0% lower than base models individually. This is the first study that uses a reduced number of IMU sensors to estimate kinematics in multiple walking environments.</div>


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