Prediction of the Lower Extremity Muscle Forces During Stair Ascent and Descent

2008 ◽  
Author(s):  
Ali Selk Ghafari ◽  
Ali Meghdari ◽  
Gholam Reza Vossoughi
Keyword(s):  
Lower Extremity ◽  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Optimization Technique ◽  
The Elderly ◽  
Plantar Flexors ◽  
Stair Ascent ◽  
Lower Extremity Muscle ◽  
Anatomical Classification ◽  
Muscle Groups

An inverse dynamics musculoskeletal model of the lower extremity was combined with an optimization technique to estimate individual muscular forces and powers during stair ascent and descent. Eighteen Hill-type musculotendon actuators per leg were combined into the eleven functional muscle groups based on anatomical classification to drive the model in the sagittal plane. Simulation results illustrate the major functional differences in plantar flexors of the ankle and extensors of the knee and hip joints during ascent and descent. The results of this study not only could be employed to evaluate the rehabilitation results in the elderly but also could be used to design more anthropometric assistive devices with optimum power consumption.

Influence of Bicycle Seat Tube Angle and Hand Position on Lower Extremity Kinematics and Neuromuscular Control: Implications for Triathlon Running Performance

2011 ◽  
Vol 27 (4) ◽  
pp. 297-305 ◽  
Author(s):  
Amy Silder ◽  
Kyle Gleason ◽  
Darryl G. Thelen
Keyword(s):  
Lower Extremity ◽  
Neuromuscular Control ◽  
Rectus Femoris ◽  
Body Motion ◽  
Treadmill Running ◽  
Whole Body ◽  
Knee Extensors ◽  
Hand Position ◽  
Plantar Flexors ◽  
Lower Extremity Muscle

We investigated how varying seat tube angle (STA) and hand position affect muscle kinematics and activation patterns during cycling in order to better understand how triathlon-specific bike geometries might mitigate the biomechanical challenges associated with the bike-to-run transition. Whole body motion and lower extremity muscle activities were recorded from 14 triathletes during a series of cycling and treadmill running trials. A total of nine cycling trials were conducted in three hand positions (aero, drops, hoods) and at three STAs (73°, 76°, 79°). Participants also ran on a treadmill at 80, 90, and 100% of their 10-km triathlon race pace. Compared with cycling, running necessitated significantly longer peak musculotendon lengths from the uniarticular hip flexors, knee extensors, ankle plantar flexors and the biarticular hamstrings, rectus femoris, and gastrocnemius muscles. Running also involved significantly longer periods of active muscle lengthening from the quadriceps and ankle plantar flexors. During cycling, increasing the STA alone had no affect on muscle kinematics but did induce significantly greater rectus femoris activity during the upstroke of the crank cycle. Increasing hip extension by varying the hand position induced an increase in hamstring muscle activity, and moved the operating lengths of the uniarticular hip flexor and extensor muscles slightly closer to those seen during running. These combined changes in muscle kinematics and coordination could potentially contribute to the improved running performances that have been previously observed immediately after cycling on a triathlon-specific bicycle.

scholarly journals The effect of stride length on lower extremity joint kinetics at various gait speeds

2018 ◽  
Author(s):  
Robert L. McGrath ◽  
Melissa L. Ziegler ◽  
Margaret Pires-Fernandes ◽  
Brian A. Knarr ◽  
Jill S. Higginson ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Gait Speed ◽  
Stride Length ◽  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Gait Training ◽  
Joint Moment ◽  
Joint Moments ◽  
Joint Kinetics ◽  
Trailing Limb Angle

AbstractRobot-assisted training is a promising tool under development for improving walking function based on repetitive goal-oriented task practice. The challenges in developing the controllers for gait training devices that promote desired changes in gait is complicated by the limited understanding of the human response to robotic input. A possible method of controller formulation can be based on the principle of bio-inspiration, where a robot is controlled to apply the change in joint moment applied by human subjects when they achieve a gait feature of interest. However, it is currently unclear how lower extremity joint moments are modulated by even basic gaitspatio-temporal parameters.In this study, we investigated how sagittal plane joint moments are affected by a factorial modulation of two important gait parameters: gait speed and stride length. We present the findings obtained from 20 healthy control subjects walking at various treadmill-imposed speeds and instructed to modulate stride length utilizing real-time visual feedback. Implementing a continuum analysis of inverse-dynamics derived joint moment profiles, we extracted the effects of gait speed and stride length on joint moment throughout the gait cycle. Moreover, we utilized a torque pulse approximation analysis to determine the timing and amplitude of torque pulses that approximate the difference in joint moment profiles between stride length conditions, at all gait speed conditions.Our results show that gait speed has a significant effect on the moment profiles in all joints considered, while stride length has more localized effects, with the main effect observed on the knee moment during stance, and smaller effects observed for the hip joint moment during swing and ankle moment during the loading response. Moreover, our study demonstrated that trailing limb angle, a parameter of interest in programs targeting propulsion at push-off, was significantly correlated with stride length. As such, our study has generated assistance strategies based on pulses of torque suitable for implementation via a wearable exoskeleton with the objective of modulating stride length, and other correlated variables such as trailing limb angle.

scholarly journals Relationships between lower extremity strength and the multi-directional reach test in children aged 7 to 12 years

2019 ◽  
Vol 39 (02) ◽  
pp. 143-150
Author(s):  
Benjaporn Hirunyaphinun ◽  
Soontharee Taweetanalarp ◽  
Anong Tantisuwat
Keyword(s):  
Lower Extremity ◽  
Flexor Muscle ◽  
Limits Of Stability ◽  
Knee Flexor ◽  
Lower Extremity Muscle ◽  
Lower Extremity Strength ◽  
Flexor Muscles ◽  
Muscle Groups ◽  
Control Balance ◽  
Hip Flexor

Objective: This study investigates the relationships between the Multi-Directional Reach Test (MDRT) and lower extremity strength in typical children. Methods: The MDRT including forward, backward, leftward, and rightward directions was measured in 60 children aged between 7 and 12 years old with typical development. The lower extremity muscle groups were measured using a hand-held dynamometer. Results: The reaching score in each direction had positive relationships with the strengths of several lower extremity muscle groups ([Formula: see text] to [Formula: see text]). Only the strengths of the hip flexor and knee flexor muscles significantly correlated with the MDRT scores in all directions ([Formula: see text] to [Formula: see text]). Conclusion: This study highlights the strength of the hip and knee flexor muscle groups as being important domain to control balance in all directions. These findings may be used for therapists in planning a balance program to improve the limits of stability.

A Biomechanical Study of Side Steps at Different Distances

2013 ◽  
Vol 29 (3) ◽  
pp. 336-345 ◽  
Author(s):  
Yuki Inaba ◽  
Shinsuke Yoshioka ◽  
Yoshiaki Iida ◽  
Dean C. Hay ◽  
Senshi Fukashiro
Keyword(s):  
Inverse Dynamics ◽  
Center Of Mass ◽  
Reaction Force ◽  
Biomechanical Study ◽  
Joint Torque ◽  
Large Power ◽  
Lower Extremity Muscle ◽  
Ankle Joints ◽  
Hip Abduction ◽  
Muscle Groups

Lateral quickness is a crucial component of many sports. However, biomechanical factors that contribute to quickness in lateral movements have not been understood well. Thus, the purpose of this study was to quantify 3-dimensional kinetics of hip, knee, and ankle joints in side steps to understand the function of lower extremity muscle groups. Side steps at nine different distances were performed by nine male subjects. Kinematic and ground reaction force data were recorded, and net joint torque and work were calculated by a standard inverse-dynamics method. Extension torques and work done at hip, knee, and ankle joints contributed substantially to the changes in side step distances. On the other hand, hip abduction work was not as sensitive to the changes in the side step distances. The main roles of hip abduction torque and work were to accelerate the center of mass laterally in the earlier phase of the movement and to keep the trunk upright, but not to generate large power for propulsion.

scholarly journals The Effects of Lower Extremity Muscle Fatigue on Dynamic Balance in Volleyball Players

2021 ◽  
Vol 19 (1) ◽  
pp. 51-58
Author(s):  
Nastaran Ghotbi ◽  
Keyword(s):  
Lower Extremity ◽  
Muscle Fatigue ◽  
Repeated Measures ◽  
Dynamic Balance ◽  
Knee Extensors ◽  
Balance Test ◽  
Lower Extremity Muscle ◽  
Adductor Muscles ◽  
Volleyball Players ◽  
Muscle Groups

Objectives: Lower extremity muscles are critical for maintaining dynamic balance and athletic performance. Fatigue of these muscles may affect dynamic balance. It is unclear whether fatigue in a particular muscle group can affect dynamic balance more than that in other groups. This study was conducted to evaluate and compare the effects of fatigue in 5 muscle groups on dynamic balance in volleyball players. Methods: Fifteen healthy male volleyball players separately performed the Star Excursion Balance Test before and immediately after the occurrence of fatigue of ankle Plantar Flexor (PF), knee extensor, knee flexor, hip abductor, and hip adductor muscles. Composite reach distance and distance in anterior, posteromedial, and posterolateral directions were recorded, accordingly. Results: Repeated-measures Analysis of Variance (ANOVA) data indicated that fatigue of all muscle groups significantly decreased the mean score of composite (P<0.001). Anterior, posteromedial, and posterolateral distance scores decreased following muscle fatigue of knee extensors and ankle PFs (P<0.05). Discussion: This study suggested that regarding composite reach score, fatigue of ankle, knee, and hip muscles similarly decreased dynamic balance. However, evaluating three main directions revealed that knee extensors and ankle PFs muscles fatigue presented more prominent effects on the explored volleyball players’ balance, compared to the other muscles.

scholarly journals Joint Torque and Mechanical Power of Lower Extremity and Its Relevance to Hamstring Strain during Sprint Running

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Yunjian Zhong ◽  
Weijie Fu ◽  
Shutao Wei ◽  
Qing Li ◽  
Yu Liu
Keyword(s):  
Lower Extremity ◽  
Stance Phase ◽  
Swing Phase ◽  
Joint Torque ◽  
Mechanical Power ◽  
Movement Direction ◽  
Joint Torques ◽  
Sprint Running ◽  
Lower Extremity Muscle ◽  
Muscle Groups

The aim of this study was to quantify the contributions of lower extremity joint torques and the mechanical power of lower extremity muscle groups to further elucidate the loadings on hamstring and the mechanics of its injury. Eight national-level male sprinters performed maximum-velocity sprint running on a synthetic track. The 3D kinematic data and ground reaction force (GRF) were collected synchronously. Intersegmental dynamics approach was used to analyze the lower extremity joint torques and power changes in the lower extremity joint muscle groups. During sprinting, the GRF during the stance phase and the motion-dependent torques (MDT) during the swing phase had a major effect on the lower extremity movements and muscle groups. Specifically, during the stance phase, torque produced and work performed by the hip and knee muscles were generally used to counteract the GRF. During the swing phase, the role of the muscle torque changed to mainly counteract the effect of MDT to control the movement direction of the lower extremity. Meanwhile, during the initial stance and late swing phases, the passive torques, namely, the ground reaction torques and MDT produced by the GRF and the inertial movement of the segments of the lower extremity, applied greater stress to the hamstring muscles.

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