Support Leg Research Articles

Correlation between the biomechanical characteristics and stability of the 143D movement during the balance phase in competitive Tai Chi.

To explore the biomechanical factors affecting the stability of athletes in the 143D balance phase of competitive Tai Chi. The Vicon 3D motion capture system, Kistler 3D force platform, and Noraxon surface electromyography (sEMG) system were used to measure the joint angle, joint moment, center of gravity, ground reaction force, and sEMG data of athletes. The stability index was then calculated according to the formula. Pearson's or Spearman's correlation tests were used to analyze the associations between the biomechanical factors and stability index. (1) Medial lateral stability index (MLSI): A significant negative correlation was found between the ankle inversion angle of the supporting leg (SL) and MLSI (p < 0.05). (2) Anterior posterior stability index (APSI): Significant negative correlations were observed between the ankle intorsion angle, integrated electromyography (iEMG) of the gastrocnemius, and muscle contribution rates of the tibialis anterior, external oblique, and gastrocnemius of the non-supporting leg (NL) with the APSI (p < 0.05). The ankle dorsiflexion moment, iEMG of the rectus femoris and tibialis anterior, muscle contribution rate of the biceps femoris, and root mean-squared (RMS) amplitude of the gluteus maximus of the SL also showed significant negative correlations with the APSI (p < 0.05). Strong and significant negative correlations were also identified between the hip intorsion angle, iEMG of the tibialis anterior, and RMS amplitude of the rectus femoris of the NL with the APSI (p < 0.01). Further strong and significant negative correlation was also found between the RMS amplitude of the biceps femoris of the SL and APSI (p < 0.01). The knee extorsion angle of the NL was positively correlated with the APSI (p < 0.05). (3) Dynamic postural stability index (DPSI): The knee adduction angle, iEMG of the tibialis anterior, and RMS amplitude of the erector spinae of the NL were significantly positively correlated with the DPSI (p < 0.05). The knee abduction and hip extension moments of the SL were also significantly positively correlated with the DPSI (p < 0.05). The ankle inversion angle of the SL impacts left-right stability, while the NL's hip and ankle intorsion angles, knee extorsion angle, and exertion on the core muscle and SL's main muscles, as well as exertion of specific muscles of the NL affect anterior-posterior stability. The hip extension and knee abduction moments of the SL, knee adduction angle, exertion on the tibialis anterior, and activation of the erector spinae of the NL significantly affect the overall stability of an athlete.

Examination of the effect of air gaps on impact sound insulation performance of dry-type double floor system

The dry-type double floor system is a floor finishing structure widely installed for apartments and offices in Japan. However, after installing the double floor system, it is found that the impact sound insulation performance using a heavy-weight impact source is usually reduced due to the resonance of the air layer between the floor panels and the concrete slab. To reduce this adverse effect, small air gaps are set between the floor panels and the surrounding walls. In this paper, an experimental study is conducted firstly. A small specimen including particle board, support legs and air gaps is made to examine the effect of air gaps experimentally. Then, the air gaps are built as a Maxwell model considering that the air gaps act as the orifice of air spring. The theoretical analysis is conducted to explain the mechanism of impact sound insulation of the double floor system with or without air gaps. Finally, a parametric study is conducted to investigate the effect of air gaps with different dimensions on the impact sound insulation performance of the double floor system.

Reduction In Support Leg Active Range Of Motion And Increase In Postural Sway On People With Chronic Low Back Pain During Y-balance Test

Reduction In Support Leg Active Range Of Motion And Increase In Postural Sway On People With Chronic Low Back Pain During Y-balance Test

Foot Dimension among Indian Population: A Pilot Study

Foot anthropometry involves measuring the dimensions and shapes of the human foot, crucial for designing footwear that improves athletic performance and reduces the risk of injuries by offering adequate support and matching natural biomechanics. This study aimed to gather foot anthropometric data from both males and females and compare foot dimensions between the two to develop specific footwear. A total of 204 male and female volunteers, with an average age of 28.20 ± 12.95 years, participated in the study, and 15-foot measurements were taken using 3D foot scanner equipment. All data was analyzed using SPSS software version 26. The Mann-Whitney U test was used to compare differences between the right and left feet of males and females. Significant differences were found in various measurements of the left feet, including 'foot length', 'foot width', 'heel circumference', 'toe circumference', 'waist circumference', 'ankle circumference', 'thumb height', 'toe width', 'heel center width', 'lateral malleolus length', 'medial malleolus length', 'Spherion height', and 'instep circumference'; however, no significant difference was observed in 'foot arch height'. This study also showed that all parameters differed significantly between the right and left feet in both males and females. The Kruskal-Wallis ANOVA test revealed no significant difference in ‘foot arch height’ between males and females, but thumb height did show a significant difference between the left and right feet of females. These precise anthropometric measurements are crucial for ensuring the proper fit of footwear, insights into this variability, allow makers to make footwear that accommodates a wide range of users enhancing control, stability, and response during daily activity. Different activity requires different leg movements and support, and precise foot anthropometry can help customize footwear to meet the unique requirements of each activity.

Structural Design and Analysis of Portable Intelligent Wheelchair for Knee Rehabilitation

In order to address the issues of inconvenience, high medical costs, and lack of universality associated with traditional knee rehabilitation equipment, a portable intelligent wheelchair for knee rehabilitation was designed in this study. Based on the analysis of the knee joint's structure and rehabilitation mechanisms, an electric pushrod-driven rehabilitation institution was developed. A multi-functional module was designed with a modular approach, and the control of the wheelchair body and each functional module was implemented using an STM32 single-chip microcomputer. A three-dimensional model was established using SolidWorks software. In conjunction with Adams and Ansys simulation software, kinematic and static analyses were conducted on the knee joint rehabilitation institution and its core components. A prototype was constructed to verify the equipment's actual performance. According to the prototype testing, the actual range of motion for the knee joint swing rod is 15.1°~88.9°, the angular speed of the swing rod ranges from -7.9 to 8.1°/s, the angular acceleration of the swing rod varies from -4.2 to 1.6°/s², the thrust range of the electric pushrod is -82.6 to 153.1 N, and the maximum displacement of the load pedal is approximately 1.7 mm, with the leg support exhibiting a maximum deformation of about 1.5 mm. The intelligent knee joint rehabilitation wheelchair meets the designed functions and its actual performance aligns with the design criteria, thus validating the rationality and feasibility of the structural design.

Treatment of Achilles tendon rupture in a patient with alkaptonuric ochronosis

The treatment result of a patient with spontaneous rupture of the Achilles tendon and features of diagnosing alkaptonuric ochronosis, a rare disease, are presented, providing doctors beneficial information for the prevention and/or delay of possible complications. On March 8, 2021, at about 20:50, while at his workplace, getting up from his chair from the table, patient K, 52 years old, felt a sharp pain in the lower third of his right shin and was urgently taken to the hospital. He was examined by a traumatologist and was initially diagnosed with rupture of the right Achilles tendon. His right lower limb was immobilized with a plaster splint. On March 11, 2021, he entered the military traumatology and orthopedics clinic of the Kirov Military Medical Academy for surgical treatment. Upon admission, the patient complained of pain in the right lower leg and impaired support function of the right lower limb. Based on complaints, medical history, laboratory results, and instrumental studies, subcutaneous rupture of the right Achilles tendon was diagnosed. On March 12, 2021, anchor suture of the right Achilles tendon was performed. Anesthesia — combined, access: two separate incisions on the posterior surface of the lower third of the right leg and in the area of the calcaneal tubercle, each 5 cm long, intraoperatively revealed a complete subcutaneous rupture of the right Achilles tendon. Notably, the tendon was black in color when cut. The postoperative period proceeded without complications, and postoperative wounds of linear shape in the right Achilles tendon healed by primary intention. No signs of disturbances were observed in peripheral circulation and innervation of the right lower limb. To confirm the diagnosis, a simple laboratory test was performed: a change in the color of urine during the day, after its additional alkalization. The color change is due to the polymerization of homogentisic acid, which is excreted in large quantities in the urine. To verify the diagnosis, a molecular genetic technique was performed: sequencing of the clinically significant HGD gene and encoding the enzyme homogentisate-1,2-dioxygenase, which are mutations that lead to alkaptonuria. The analysis results confirmed the presence of an amino acid substitution at the pGLy161Arg position, indicating pathogenicity. The use of simple methods of additional laboratory diagnostics and molecular genetic analysis enabled the diagnosis of alkaptonuric ochronosis. Thus, characteristic diagnostic signs were damage to the Achilles tendon in combination with the obtained anamnestic, clinical, and laboratory data of alkaptonuria.

Application of deep learning classification model for regional evaluation of roof pressure support evolution effects over time in coal mining face

Hydraulic support leg pressure serves as a crucial indicator for assessing work face support quality. Current evaluation methods for support quality primarily concentrate on static analyses-like inadequate initial support force, pressure overrun, and uneven bracket force-while neglecting dynamic column pressure changes. This paper introduces a model for assessing hydraulic support quality using deep learning techniques. Real-time data is preprocessed into a spatio-temporal pressure sub-matrix sample, which is then inputted into the model. This process assesses the support quality type and characterizes its dynamic evolution within the area. The model facilitates the identification of dynamic support quality effects in the working face area, aiding operators in making targeted adjustments to hydraulic support status. Experimental results revealed that the optimized LeNet-5 network-adjusting parameters like convolutional layer count, kernel size, and ReLU activation function-achieved the highest classification accuracy of 85.25 % for support quality, surpassed other networks. Furthermore, the improved LeNet-5 network outperformed other networks in both F1 score and recall. Additionally, the improved LeNet-5 network achieved faster convergence to the optimal solution, accelerated training speed. This highlighted its advantages in evaluating the spatio-temporal support quality of hydraulic supports in smart mining operations.

Does swing leg braking matter in long jump take-off? A 3-D kinematic analysis based on elite athletes

The objective of this study was to explore the braking technical characteristics of the swing leg of elite male athletes in long jump take-off and its dependencies on the extension velocity of the support leg and the balance. Two cameras were used to capture 8 elite male long jump athletes (25.88 ± 3.00 years) under competitive conditions at a National Indoor Athletic Championships Final, a 3-D kinematic analysis method was conducted to analyze the take-off technique of the athletes. The results showed that the rapid braking of the swing leg increased the extension velocity of the support leg. Compared to the swing leg that started braking at the moment of maximum knee flexion of the support leg (SPKnee maximum flexion moment), athletes’ performance was greater when swing leg started braking at the moment of maximum ankle flexion of the support leg (SPAnkle maximum flexion moment). Furthermore, the swing leg exhibited an inward movement during its forward swing, and the inward angle was significantly correlated with the balance maintenance (r = - 0.50,P = 0.004). In conclusion, a relatively delayed rapid braking and moderate inward movement of the swing leg during the take-off phase are conducive to achieving a better take-off effect in long jump.

ФОРМАЛИЗМ РЕШЕНИЯ ПЕРВОЙ ЗАДАЧИ ДИНАМИКИ ШАГАЮЩИХ И КОЛЕСНО-ШАГАЮЩИХ МАШИН

The aim is to solve the first problem of the dynamics of machines moving their bodies with the help of legs, i.e., to calculate the control actions of the leg actuators that provide the given dynamics of the absolute motion of the body and satisfy the constraints, when fulfilled, there is no sliding of the supporting legs relative to the supporting surface. The research methods are related to system analysis, mechanics of body systems and robotics. We consider walking and wheel-walking machines with legs suspended from the body, in which the last kinematic pair is translational, there is no controlled foot, and the foot and the supporting surface interact at a single point. The resultsof the study contain analytical formulas for calculating dynamic reactions at the points of contact between the legs and the supporting surface, as well as driving forces and moments of forces in the drives of the supporting and carrying legs, providing a given motion of the body relative to the supporting surface, as well as its corresponding relative motion of the bodies of the supporting legs. A formalism for solving such problems is described, based on inverse vector recurrence formulas for calculating forces and moments of forces of dynamic reactions in kinematic pairs of tree-like systems of bodies with closure of the last body of the branch on the supporting surface. This formalism is extended to wheeled, wheel-walking and walking machines, which is demonstrated by appropriate examples. Analytical conditions for realizing a step without slipping of the support legs relative to the support surface are written down. Two simple wheel-walking machines, consisting of a linear electric drive and a driven (passive) wheelset, are proposed for the experimental determination of sliding and rolling friction coefficient values. In analytical forms of deduced calculation formulas (equations and inequalities) the structural, geometric, inertial and kinematic parameters of the investigated machines are explicitly expressed. The proposed formalism is demonstrated on the solutions of four problems from simple to complex through the reuse of formulas. Conclusion. The obtained mathematical models can be used in the processes of calculation and design of similar machines and their layouts.

Peran Zakat, Infaq dan Sedekah dalam Meningkatkan Kesejahteraan Difabel Cerebral Palsy melalui Program Jombang Sehat: Studi pada BAZNAS Jombang

Cerebral palsy is a child with special needs where cerebral paralysis occurs, which causes disturbances in the development and growth processes both physically and emotionally. People with cerebral palsy require special attention and regular care, which requires assistance. So, based on this problem, researchers want to examine how much ZIS funds are utilized for people with cerebral palsy, specifically in the Jombang Regency area. The type of research used is a descriptive qualitative approach. Descriptive qualitative research is a type of research in which a researcher investigates events and phenomena in the lives of individuals and asks a person or group of individuals to talk about their lives. The information obtained by the researcher is retold. by researchers in descriptive chronology. In this research, the data used is qualitative data sourced from primary data and secondary data. Primary data is collected through interviews and documents, and secondary data is analyzed through financial reports and annual magazines at BAZNAS Jombang Regency. This research shows that the distribution of Zakat, Infaq, and Alms at BAZNAS Jombang Regency has a role in improving the welfare of mustahiks who suffer from cerebral palsy. This role includes providing milk or nutritional assistance, vitamins, snacks, leg support, routine therapy every week, and helping the mustahik's daily economy.

Motion planning and contact force distribution for heavy‐duty hexapod robots walking on unknown rugged terrains

AbstractHeavy‐duty hexapod robots have impressive stability, high load‐bearing capacity, and exceptional adaptability to rugged terrains. They are capable of working in challenging outdoor environments such as planetary exploration, disaster relief and mountain transportation. Their ability to traverse terrain requires effective motion planning and accurate force distribution, neither of which is currently at the level required for widespread practical applications. In this paper, the mechanical legs are divided into support and swing legs, and the adaptability of the hexapod robot to unknown rugged terrain is enhanced by introducing the Decomposition Quadratic Programming‐based Contact Force Distribution (DQP‐based CFD) method. Moreover, an efficient replanning strategy can handle accidental collisions between swinging legs and unmodelled obstacles. Extensive field experiments demonstrate the effectiveness of our proposed motion planning and contact force distribution methods.

Pilot study: Effect of Developmental Dysplasia of the Hip on the Gait and Feet Posture

Background: The objective of this pilot study was to assess the effect of Developmental Dysplasia of the Hip (DDH) on gait, in pediatric participants, between the age of one to four years. Few studies are investigating the effect of DDH on the walking pattern within the pediatric rehabilitation practice. From an early age, children are developing a longitudinal foot arch. Constantly changing pediatric foot posture must be assessed. Gait pattern and foot posture are one of the most common parental concerns.&#x0D; Methods: The retrospective review of gait analysis, performed on 410 lower limbs, took place in King Abdullah Specialized Children Hospital (KASCH) in Riyadh, Kingdom of Saudi Arabia, from April 2020 until September 2020. All participants were diagnosed with DDH by pediatric orthopedics physicians in KASCH. Gait analysis was done by a physical therapist twice within three months, using The Wee Glasgow Gait Index (WeeGGI) and foot assessment was done once using Foot Postural Index (FPI-6). The WeeGGI compares eleven gait parameters. Each parameter has a choice of three figures, where each one has a clear explanation and/or value. The FPI-6 evaluates the foot as multi-segmental complex, in double leg support, characterizing pronation with + (plus) and supination with - (minus) numbers. Scoring is 2 (two) points in all six factors it is divided into rearfoot and forefoot assessment in transverse, frontal/transverse, frontal, and sagittal planes.&#x0D; Results: From all gait analyses (n=410). We included only 292 (71%) lower limbs with DDH and had to exclude 60 (15%) after hip surgery, 30 (7%) with another diagnosis, 18 (4%) without conservative treatment of DDH, and 10 (3%) with age above 48 months. According to the scoring of the Wee Glasgow Gait Index within the optimum/normal limits (score 0 - zero), we had 50 (17%), mild deviation (score 1-11) 236 (81%), and gross deviation (score 12-22) had 6 (2%) limbs within first gait analysis. With second gait analysis, 40% of lower limbs were within optimum/normal limits, 60% with mild deviation in gait, and zero within gross deviation. Every limb assessment for gait had the Foot Postural Index as well. Within normal limits (0 till +5) we had 143 (49%) feet, pronation (+6 till +9) was presented in 97 (33%) and high pronation (more then +10) had 52 (18%) pediatric feet. This sample did not present supination (-1 till -4) or high supination (-5 till -12). Limping was observed within 102 (35%) of the legs. The frequency of W-sitting presented in 47% of the results. The first and second gait analysis suggest an effect of DDH on the gait with a small difference between the right and left leg, although the left side was affected more within both gait analyses.&#x0D; Conclusion: Pathological gait pattern with DDH was detected in 83% within the first gait analysis, 60% within the second gait analysis, and Foot Postural Index revealed pronation of 51% feet. Among Saudi participants, a relatively high effect of DDH on gait patterns is reported in this pilot study.&#x0D; Keywords: DDH, gait, FPI-6, physiotherapy, WeeGGI.

Walking control of semi-passive robot via a modified Q-learning algorithm

The analysis and control of stability of passive biped robot has been the subject of an in-depth study because of its unique characteristics. This work gives a new perspective aiming at a force applied on foot of collision phase of walking process of passive robot, which is a completely new way of applying impulse force that is different from the previous. Therefore, the new equation has been derived due to this force which is not parallel to the support leg to provide further analysis for the study. Besides, this paper combines the characteristics of passive walking with the process of reinforcement learning, and an improved algorithm thus was designed to calculate the value of the control force. The simulation results show that control method designed in this article can not only make the unsteady passive robot achieve stable walking, but also have a quick control speed. Furthermore, the selection range of initial values is expanded by using this method, which provides a convenient reference for the later research work.

The Effect of Variations in Knee and Hip Angles on Electromyographic Activity of the Hamstrings and Related Muscles During the Nordic Hamstring Exercise.

The benefit of performing the Nordic Hamstring Exercise (NHE) on an inclined board has been described, however, isometric hamstring activation in different knee and hip angles has not yet been thoroughly explored. This study investigated the effect of variations in knee and hip angles during the isometric performance of the NHE on electromyographic activity of the hamstring muscles. Crossover study. Thirteen male volunteers performed isometric contractions during the NHE with the knee (30°, 50°, 60°) and the hip (0°, 30°, and 45°) in various angles of flexion on a leg support platform which was inclined at 30°. An electrical goniometer was used to monitor the knee and hip joint angles during 5-s isometric contractions. A multivariate analysis of variance with repeated measures was used to compare normalized electromyographic values of each muscle across different knee and hip angles, followed by pairwise comparisons. The electromyographic activity of the biceps femoris, semitendinosus, and semimembranosus at a knee angle of 30° and hip angle of 0° were significantly higher than those observed with a knee angle of 50° and hip angle of 0°, or a knee angle of 60° and hip angle of 0° (p<0.05). The electromyographic activity of the semimembranosus at a knee angle of 60° and hip angle of 45° was significantly higher than values obtained with knee and hip angles of 60° and 0°, respectively (p<0.05). The results indicate that using a knee flexion of 30° and a hip flexion of 0°, while isometrically performing the NHE on a platform inclined at 30°, may optimize electromyographic activity of the hamstrings. 3.

Structural design and research of a novel lower limb rehabilitation robot for human–robot coupling

A bedside rehabilitation robot is developed to address the challenge of motor rehabilitation for patients with lower limb paralysis. Firstly, based on the principles of physical rehabilitation, a two-link planar robot model is used to simulate both the robot and human lower limbs, and the coupling characteristics between the human and robot are thoroughly analyzed. Then, the lower limb rehabilitation robot, fitted with an end-effector and ankle wearable feature, is designed according to the structural parameters. To enhance patient safety during rehabilitation, the device incorporates a freely rotating leg support mechanism that reduces the load on the ankle due to gravitational forces, and a two-stage series elastic mechanism is integrated below the foot support to provide a passive compliant output of robot power, allowing for more natural movement and reducing the risk of injury. Secondly, dynamic modeling is used to determine the dynamic parameters of the robot by conducting simulation calculations based on the inertia parameters of the human body and the robot model design parameters. Finally, an experimental platform is established using the structural and dynamic parameters, and the robot’s reliability is validated through experimentation. Results indicate that the robot can accurately complete passive rehabilitation training tasks, and the dynamic parameters meet the expected requirements.

Concurrent training associated with moderate walnut consumption improved isokinetic strength, subjective sleep quality, cognitive performance and postural balance in elderly active men: a randomized controlled trial

AimsTo investigate the effects of concurrent training (resistance and endurance) associated with moderate walnut consumption on isokinetic strength, subjective sleep quality, cognitive performance and postural balance in physically active elderly men.MethodsTwenty healthy elderly men were divided into two matched groups, in a randomized controlled experiment. They have participated in three training sessions per week: concurrent (strength and endurance) training + ad libitum diet with walnuts (15 g/day for 6 weeks, CTW: n = 10) and concurrent training + ad libitum diet (CT: n = 10). Isokinetic strength, Spiegel questionnaire, Montreal cognitive assessment and postural balance parameters were assessed 48 h pre- and post-intervention.ResultsAbsolute peak torque of knee extensors and knee flexors significantly increased compared to pre-training in CTW (15.2% ± 6.7; 13.2% ± 2.3, p < 0.05, respectively) and CT (10.6% ± 6.8; 7.4% ± 2.9, p < 0.05, respectively). Subjective sleep quality increased compared to pre-training for CTW and CT (24% ± 14.4; 10.5% ± 9.4, p < 0.05, respectively) with a significantly greater increase in CTW (p < 0.05). Cognitive performance measured by Montreal cognitive assessment (MoCA) increased only in CTW compared to baseline (7.7% ± 2.5, p < 0.05). Postural balance parameters with dual task decreased only in CTW compared to baseline.ConclusionsThe present study clearly revealed that concurrent training alone or associated with daily walnut (15 g) consumption for 6 weeks significantly increased knee isokinetic strength, support leg standing parameters and sleep quality. Meanwhile, cognitive performance evaluated by MoCA test and postural balance with dual task were improved for CTW group only.

Anticipatory postural control in adaptation of goal-directed lower extremity movements.

Skilled football players can adapt their kicking movements depending on external environments. Predictive postural control movements, known as anticipatory postural adjustments (APAs), are needed preceding kicking movements to precisely control them while maintaining a standing posture only with the support leg. We aimed to clarify APAs of the support leg in the process of adaptation of goal-directed movements with the lower limb. Participants replicated ball-kicking movements such that they reached a cursor, representing a kicking-foot position towards a forward target while standing with the support leg. APAs were observed as the centre of pressure of the support leg shifted approximately 300ms in advance of the onset of movement of the kicking foot. When the cursor trajectory of the kicking foot was visually rotated during the task, the kicking-foot movement was gradually modified to reach the target, indicating adaptation to the novel visuomotor environment. Interestingly, APAs in the mediolateral direction were also altered following the change in kicking-foot movements. Additionally, the APAs modified more slowly than the kicking-foot movements. These results suggest that flexible changes in predictive postural control might support the adaptation of goal-directed movements of the lower limb.

Experimental comparison of leveling control schemes for the hyperstatic-leg support platform

Leveling control for the platform with four or more legs is the technical mainstay in outrigger leveling of truck cranes, height and leveling control of vehicles, etc. Due to the “implicated coupling” between the platform and legs, the addition of one leg will cause a significant increase in leveling time, severe oscillations in leveling process, deterioration in accuracy and stability, and even leveling failure. For evaluating and selecting an appropriate leveling control scheme, in terms of leveling theory, three control schemes based on the dominant point chasing principle, That is, lowest-point regulation, cyclic regulation, and synchronous regulation, are studied, in which the virtual leg compensation is carefully considered. More importantly, coupling control schemes of independent geometry leveling (GCC), and synchronous geometry leveling and load uniforming (G&amp;LCC), are proposed relying on linearized coupling models established by our team. In terms of verification, considering the elastic deformation reality, electro-mechanical bench tests are conducted for a six-elastic leg support elastic platform. Results confirm that the synchronous regulation has advantages from speed, stability, and safety. And the G&amp;LCC scheme by synchronous regulation has obvious advantages in terms of leveling accuracy, speed, load controllability, and process convergence, and is of good application value for accurate, fast, and reliable leveling of hyperstatic-leg support platforms.

Design of Stair-Climbing Electric Wheelchair With Tri-Spoke Wheel and Supporting Leg

Design of Stair-Climbing Electric Wheelchair With Tri-Spoke Wheel and Supporting Leg

Relationship Between Supporting Leg Stiffness and Trunk Kinematics of the Kicking Leg During Soccer Kicking.

The stiffness of the supporting leg may alter the energy transfer to the trunk and lower extremities of the kicking leg, which may affect kick performance. This study aimed to clarify whether the stiffness of the supporting leg affects the trunk kinematics during kicking and kicking performance in soccer players. Twenty-two male collegiate soccer players participated in the study. The data for the stiffness properties of the supporting leg and trunk kinematics were obtained and calculated using a 3-dimensional motion analysis system. The results showed that a greater leg stiffness of the supporting leg was associated with a lower trunk rotation angle during kicking. There were no significant correlations between the maximum swing speed and the stiffness of the supporting leg (P < .05). These results suggest that stiffness of the supporting leg may restrain trunk rotation during the kicking motion. However, the lack of a relationship with swing speed indicates the need for further investigation into its effects on kicking performance.