Search results for "kinematics"

Kinetic and Kinematic Analysis of Iatrogenic Medial Patellar Instability: Clinical Relevance

2012

We speculate that chronic recurrent soft tissue fatigue or overload due to patellofemoral imbalance could cause anterior knee pain. However, many chondropathies can be asymptomatic due to the biomechanic defence strategies used by the patients. Moreover, we emphasize the importance of the passive restraining structures in patellar stability, in contrast to the role of muscle function advocated by some authors. This could explain why an exercise rehabilitation program could be unsuccessful in improving patellar instability, as it occurred in our cases. Finally, these cases highlight the need for surgeons to be more judicious in their surgical selection for patellofemoral instability and serv…

Postural Adjustments and Kinematic Index Finger Features in Frail Older Adults under Different Equilibrium Constraints

2021

Background: Anticipatory postural adjustments (APAs) are significantly affected by age and may represent restrictions on functional independence. Previous studies in young adults have already highlighted that changing postural stability (i.e., seated vs. upright posture) affects the motor planning and APAs. In frail older adults (FOAs), the effect of these different conditions of postural stability have not yet been established, and the present study aimed to disentangle this issue. Methods: Participants executed an arm-pointing task to reach a diode immediately after it turned on, under different conditions of stability (seated with and without foot support and in an upright posture). A ki…

Eye Kinematics of Athletes in Non-Familiar Sports Situations

2008

Biological motion can hardly be imitated, starting from how a person observes and learns motor behaviour. We recorded eye movements of 13 female ball games athletes and 13 age-matched controls observing videos of unfamiliar sports. The athletes are better at alternating between faster and slower eye movement modalities. They initially use longer but fewer fixations than the non-athletes.

2018

Beyond the classical paradigm that presents the Anticipatory Postural Adjustments (APAs) as a manner to create forces that counteract disturbances arising from the moving segment during a pointing task, there is a controversial discussion about the role APAs to facilitate the movement and perform a task accurately. In addition, arm kinematics features are classically used to infer the content of motor planning for the execution and the control of arm movements. The present study aimed to disentangle the conflicting role of APAs during an arm-pointing task in which the subjects reach a central diode that suddenly turns on, while their postural stability was manipulated. Three postures were a…

Effect of Motor-Cognitive (Dual Task) Rehabilitation Program on Gait Biomechanics in Parkinson’s Disease: Case Study

2016

In some pathologies with impaired control gait, the dual task execution even worse these gait alterations, as in Parkinson’s Disease (PD) occurs. The aim of this paper is to present the effects of a rehabilitation program that integrates dual tasks in gait rehabilitation and prepare patients to move functionally in complex environments in a person with PD. 3D photogrammetry system and two force platform were used for the registering of kinematic and kinetic parameters, respectively. The main variables that have improved after the proposed program are: speed gait (54.87 %), step length (52.01 %), stride length (43.48 %), double support time (37.36 %), flexo-extension hip range of motion (36.…

Kinematics of shoulder abduction in the scapular plane

1995

In this paper the kinematics of arm abduction in the scapular plane of 38 healthy experimental subjects is reported. The ratio of the glenohumoral and the scapulothoracic components of the motion were determined and the influence of the abduction speed and of the external load on it were investigated. The investigation of the effect of abduction speed involved all 38 subjects. Each of them performed one slow and one fast abduction. Statistical analysis showed that there were large differences between individuals, but that for any one individual the abduction process is essentially reproducible. For the one individual there is a strong, linear relationship between glenohumeral and scapulotho…

2020

Background Sprint performance is an essential skill to target within soccer, which can be likely achieved with a variety of methods, including different on-field training options. One such method could be heavy resisted sprint training. However, the effects of such overload on sprint performance and the related kinetic changes are unknown in a professional setting. Another unknown factor is whether violating kinematic specificity via heavy resistance will lead to changes in unloaded sprinting kinematics. We investigated whether heavy resisted sled training (HS) affects sprint performance, kinetics, sagittal plane kinematics, and spatiotemporal parameters in professional male soccer players…

Modification of Angular Kinematics and Spatiotemporal Parameters during Running after Central and Peripheral Fatigue

2021

Fatigue causes kinematics modifications during running, and it could be related to injuries. The aim was to identify and compare the effects of central and peripheral fatigue on angular kinematics and spatiotemporal parameters during running. Angular kinematics and spatiotemporal parameters were evaluated using an infrared motion capture system and were registered during 2 min treadmill running in pre- and post-fatigue states in eighteen male recreational runners. Central fatigue was induced by a 30 min running fatigue protocol on a treadmill, while peripheral fatigue in quadriceps and hamstrings muscles was induced by an isokinetic dynamometer fatigue protocol. Central fatigue increased th…

Die Röntgendigitalanlage als Instrument zur kinematischen Untersuchung der Schulter — Eine Untersuchung zur Strahlenbelastung - Digital Radiography a…

1991

The radiation exposure during biomechanical investigation of the shoulder joint done with a digital radiography system (Polytron 1000 VR - Siemens) was measured experimentally. Total radiation dose and surface dose were determined by phantom measurements. The radiation exposure per image is about 1/6 to 1/7 of that of a conventional study. The digital radiography system used is thus suitable for kinesiologic studies of large joints in healthy volunteers.

Foot Orthosis in Running

2019

Abstract Foot orthosis is a popular strategy for runners aiming to reduce the injury risk and improve performance in running. Companies of foot orthosis claim for a high number of benefits, however, the literature is controversy in many aspects and there are not systematic results because of the use of them. The aim of this chapter is, firstly, to introduce the reader about the concept of foot orthosis and its different definitions and types. Secondly, to show the most important scientific literature about its biomechanical and physiological effects during running. These biomechanical and physiological effects were divided into the following sections in order to be clear for the reader: kin…