Search results for "biomechanics"
showing 10 items of 281 documents
Impact Acceleration During Prolonged Running While Wearing Conventional Versus Minimalist Shoes.
2020
Purpose: In recent years a sub-group of minimalist runners have emerged who aim to perform physical exercise more naturally in an attempt to reduce running-related injuries. Here we aimed to determine the effect that running with minimalist footwear in a prolonged run has on footimpact accelerations. Method: Seventeen runners ran with minimalist and conventional shoes (MS and CS, respectively) in two separate sessions; the participants had experience with both footwear types. We measured the length and frequency of each stride, as well as the tibial and head impact acceleration every 5 minutes during a prolonged run (30 minutes at 80% of each individual's maximum aerobic speed). Results: Th…
Effect of fatigue and gender on kinematics and ground reaction forces variables in recreational runners.
2017
The presence of fatigue has been shown to modify running biomechanics. Overall in terms of gender, women are at lower risk than men for sustaining running-related injuries, although it depends on the factors taken into account. One possible reason for these differences in the injury rate and location might be the dissimilar running patterns between men and women. The purpose of this study was to determine the effect of fatigue and gender on the kinematic and ground reaction forces (GRF) parameters in recreational runners. Fifty-seven participants (28 males and 29 females) had kinematic and GRF variables measured while running at speed of 3.3 m s−1 before and after a fatigue test protocol. T…
Force Generation Profiles of Para-Nordic Sit-Skiers Representing Different Physical Impairments
2021
Abstract Purpose To biomechanically profile force generation connected to the complex role of the trunk in double poling in a representative sample of Para-Nordic sit-skiers. Methods Twelve male World Cup Para-Nordic sit-skiers (sport classes: LW10–12) were skiing on flat snow terrain at submaximal speed of 4.5 m/s (~ 73% maximum speed). 2D video (50 Hz) and pole force analyses (1000 Hz) were performed synchronously, examining angle, force and cycle characteristics to analyse the role of the trunk in generating propulsion. Results LW10–11.5 skiers lost between 21% and 4% propulsive force versus LW12 athletes only due to different geometrics of the trunk and pole angle at an equal axial pole…
The Epidemiology of Low- and High-Energy Distal Radius Fracture in Middle-Aged and Elderly Men and Women in Southern Norway
2012
Background Distal radius is one of the most frequent sites for fractures in the elderly population. Despite this, there is a paucity of epidemiological data for distal radius fracture, in particular, distinguishing between high- and low-energy fractures. Our aim was to study the epidemiology of high- and low-energy distal radius fracture in middle-aged and elderly men and women in Southern Norway, and search for associates with high- or low-energy distal radius fracture in this population. Methodology/Principal Findings Patients with distal radius fractures aged ≥50 years were identified from all four hospitals in Southern Norway between 2004 and 2005. Age-adjusted and age-specific incidenc…
Biomechanical analysis of anticipation of elite and inexperienced goalkeepers to distance shots in handball
2012
AbstractThe objective of this study was to evaluate the anticipation time and kinematic factors in the movement ofgoalkeepers’ center of mass when making a long-distance throw in handball. The sample group was composed of 14goalkeepers and field players. A force platform was used to measure the force of the goalkeepers’ reaction movements, whilethe throwers’ movements were recorded with high-speed cameras. The expert goalkeepers began to move 193 ± 67 ms beforethe ball was released, with a 67% success rate of interception. The inexperienced goalkeepers began their movement 209 ±127 ms with a 24% success rate. The time taken by expert goalkeepers to begin a vertical movement of their CM, rel…
Effects of a Postural Exercise Program on Vertical Jump Height in Young Female Volleyball Players with Knee Valgus
2022
Background: Although a knee valgus position is related to the increase in injury risk in volleyball players, there is a lack of studies on the relationship between knee valgus and vertical jump (VJ) performance. Hence, the aim of this study was to investigate the effects of a postural exercise program on VJ height in young female volleyball players with knee valgus. Methods: This pilot study included 19 young female volleyball players divided into the following groups: the Valgus Experimental Group (VEG); the Valgus Control Group (VCG); and the Neutral Control Group (NCG). All three groups carried out the same volleyball training program. In addition, only the VEG underwent a 3-month postur…
From medical data to simple virtual mock-up of scapulo-humeral joint
2008
The surgical operations of shoulder joint are guided by various principles: osteosynthesis in the case of fracture, osteotomy in order to correct a deformation or to modify the functioning of the joint, or implementation of articular prosthesis. At the end of the twentieth century, many innovations in the domains of biomechanics and orthopedic surgery have been performed. Nevertheless, theoretical and practical problems may appear during the operation (visual field of surgeon is very limited, quality and shape of the bone is variable depending on the patient). Biomechanical criteria of success are defined for each intervention. For example, the installation with success of prosthetic implan…
ICR in human cadaveric specimens: An essential parameter to consider in a new lumbar disc prosthesis design.
2020
[EN] Study design Biomechanical study in cadaveric specimens. Background The commercially available lumbar disc prostheses do not reproduce the intact disc's Instantaneous centre of Rotation (ICR), thus inducing an overload on adjacent anatomical structures, promoting secondary degeneration. Aim To examine biomechanical testing of cadaveric lumbar spine specimens in order to evaluate and define the ICR of intact lumbar discs. Material and Methods Twelve cold preserved fresh human cadaveric lumbosacral spine specimens were subjected to computerized tomography (CT), magnetic resonance imaging (MRI) and biomechanical testing. Kinematic studies were performed to analyse range of movements in or…
A public dataset of overground walking kinetics in healthy individuals
2018
The dataset comprises raw kinetic data (both in .mat and .txt) of 128 healthy subjects (52 female, 76 male; M age: 23.8 years, SD 9.1; M body height: 1.76 m, SD 0.08; M body mass: 71.3 kg, SD 13.0; M body mass index: 22.9 kg/m², SD 2.8; M gait speed: 1.33 m/s, SD 0.13) during overground walking. All subjects met the inclusion criteria, which meant that during the study, they were free of lower extremity pain or injuries. In addition, before and during the study, they were free of any gait pathology. The .mat-file 'gait_grf_subject.mat' includes six 128x1 double variables containing one row value for each of the 128 subjects: subject_id [number] subject_gender [1 = "female" ; 0 ="male"] subj…
Tonographic Effect of Ocular Response Analyzer in Comparison to Goldmann Applanation Tonometry.
2016
AIMS The tonographic effect is a phenomenon of intraocular pressure (IOP) reduction following repeated tonometry. This study examines whether the tonographic effect occurs following IOP measurement performed with Ocular Response Analyzer (ORA). METHODS Both eyes of 31 glaucoma patients and 35 healthy controls underwent nine IOP-measurements performed with GAT and ORA. The number of GAT and ORA measurements performed on each eye differed depending on the randomly allocated investigation scheme. Central corneal thickness (CCT), anterior chamber volume (ACV) and anterior chamber depth (ACD) were assessed with Pentacam before and after the repeated GAT/ORA measurements. RESULTS There was no sta…