Search results for "Locomotion"
showing 10 items of 201 documents
Effects of plyometric and pneumatic explosive strength training on neuromuscular function and dynamic balance control in 60–70year old males
2013
The present study compared neuromuscular adaptations to 12weeks of plyometric (PLY) or pneumatic (PNE) power training and their effects on dynamic balance control. Twenty-two older adults aged 60-70 (PLY n=9, PNE n=11) participated in the study. Measurements were conducted at Pre, 4, 8 and 12weeks. Dynamic balance was assessed as anterior-posterior center of pressure (COP) displacement in response to sudden perturbations. Explosive isometric knee extension and plantar flexion maximal voluntary contractions (MVCs) were performed. Maximal drop jump performance from optimal dropping height was measured in a sledge ergometer. Increases in knee extensor and ankle plantar flexor torque and muscle…
Muscle strength and mobility as predictors of survival in 75-84-year-old people.
1995
The purpose of the study was to examine the association of physical capacity, as determined on the basis of self-report and physical measurements, with survival in three groups of elderly people aged 75, 80 and 75-84 years. The main aspects of physical capacity were mobility, walking speed, hand grip strength and knee extension strength. Although 1142 persons participated in mobility interview, of whom 466 also took part in the walking speed test, and 463 in the strength tests. The follow-up periods ranged from 48 to 58 months. Risk of death was significantly related to difficulties in indoor mobility among the 75-84-year-olds (odds ratio = 1.99, 95% confidence interval = 1.27-3.13) and 75-…
Practice-Related Improvements in Postural Control During Rapid Arm Movement in Older Adults: A Preliminary Study
2012
International audience; Background. Postural control associated with self-paced movement is critical for balance in older adults. The present study aimed to investigate the effects of a virtual reality based program on the postural control associated with rapid arm movement in this population. Methods. From an upright standing position, participants performed rapid arm raising movements toward a target. Practice-related changes were assessed by pre- and posttest comparisons of hand kinematics and center of pressure displacement parameters measured in a training group (mean age: 71.50 +/- 2.67 years, n = 8) and a control group (mean age: 72.87 +/- 3.09 years, n = 8). Training group participa…
Action Representation in Patients with Bilateral Vestibular Impairments
2011
During mental actions subjects feel themselves performing a movement without any corresponding motor output. Although broad information is available regarding the influence of central lesions on action representation, little is known about how peripheral damages affect mental events. In the current study, we investigated whether lack of vestibular information influences action representation. Twelve healthy adults and twelve patients with bilateral vestibular damage actually performed and mentally simulated walking and drawing. The locomotor paths implied one (first walking task) and four (second walking task) changes in the walking direction. In the drawing task, participants drew on a she…
Influence of competition on performance factors in under-19 soccer players at national league level.
2020
The aim of this study was to analyse and quantify the acute effects of competition on several performance factors in under-19 male soccer players. To this end, 198 national league players (17.56 ± 0.78 years) performed various tests to measure jump capacity, kicking velocity and sprint times immediately pre-match (T1), at half-time (T2) and post-match (T3). Tests included kicking the ball to measure ball velocity (KICK), sprinting for 40 meters, timing the first 30 meters (30mACCEL), the last 10 meters (10mACCEL) and the total distance (40mACCEL), and performing countermovement jumps (CMJ). For subsequent analysis, the sample was divided into 5 playing positions: goalkeepers (n = 24), defen…
Mice lacking α-synuclein display functional deficits in the nigrostriatal dopamine system
2000
alpha-Synuclein (alpha-Syn) is a 14 kDa protein of unknown function that has been implicated in the pathophysiology of Parkinson's disease (PD). Here, we show that alpha-Syn-/- mice are viable and fertile, exhibit intact brain architecture, and possess a normal complement of dopaminergic cell bodies, fibers, and synapses. Nigrostriatal terminals of alpha-Syn-/- mice display a standard pattern of dopamine (DA) discharge and reuptake in response to simple electrical stimulation. However, they exhibit an increased release with paired stimuli that can be mimicked by elevated Ca2+. Concurrent with the altered DA release, alpha-Syn-/- mice display a reduction in striatal DA and an attenuation of …
Gross motor proficiency and intellectual functioning
2018
Abstract This cross-sectional study examines differences in gross motor proficiency as a function of different intellectual functioning profiles. Two motor areas have been investigated as being equally essential to gross motor functions in every-day life: locomotion and object control. It aims to compare gross motor skills endorsed by children with Down syndrome (DS), children with borderline intellectual functioning (BIF), and typically developing children (TDC). Group 1 was composed of 18 children with DS (chronological age = 8.22), group 2 was composed of 18 children with BIF (chronological age = 9.32), and group 3 was composed of 18 children with typical development (TD) (chronological …
Weak phylogenetic effects on ecological niches of Sylvia warblers
2003
To understand the evolution of ecological niches it is important to know whether niche evolution is constrained by phylogeny. We approached this question for Sylvia warblers by testing if closely related species are more similar in 20 ecologically relevant morphological traits than distantly related species. Phylogenetic relatedness was quantified using a molecular phylogeny based on the mitochondrial cytochrome b gene. By Principal Component Analysis (PCA) two major niche axes were extracted. We tested the individual ecomorphological traits and the positions of the species on the PCA axes for phylogenetic effects using Mantel tests. The results demonstrated small but significant phylogenet…
Analysis of the impact of a cognitive task on the posture of elderly subjects with depression compared with healthy elderly subjects
2016
International audience; Objective: While previous studies have demonstrated that depressive elderly subjects (DES) experience difficulties in the processing of simultaneous cognitive tasks, few have examined the coupling of cognitive tasks with seemingly 'automatic' tasks, such as standing upright. Current patient management focuses on pharmacological treatments and cognitive-behavioral therapies.Methods: Healthy elderly (HES) and non-treated DES were included. Postural sway in DES was compared with that in HES while in single-task and dual-task conditions. The single-task consisted of standing upright. For the dual-task, the subjects recalled various items from memory or counted while stan…
Sex differences in behavioral traits related with high sensitivity to the reinforcing effects of cocaine
2021
Cocaine is the most prevalent illegal stimulant drug in Europe among the adult population. Its abuse is characterized by a faster substance abuse disorder (SUD) development than other drugs, with high vulnerability to relapse. However, there does not exist an effective treatment for cocaine dependence. Sex differences have been reported in psychological disorders including SUD. For this reason, it is essential to identify risk factors that predict susceptibility or resilience to cocaine addiction for the development of effective prevention strategies considering sex differences. In the present study, the main objective was to determine more sensitive phenotypes to the conditioned reinforcin…