Search results for "Move"
showing 10 items of 2153 documents
Age-related neuromuscular function during drop jumps.
2007
Muscle- and movement-specific fascicle-tendon interaction affects the performance of the neuromuscular system. This interaction is unknown among elderly and consequently contributes to the lack of understanding the age-related problems on neuromuscular control. The present experiment studied the age specificity of fascicle-tendon interaction of the gastrocnemius medialis (GM) muscle in drop jump (DJ) exercises. Twelve young and thirteen elderly subjects performed maximal squat jumps and DJs with maximal rebound effort on a sledge apparatus. Ankle and knee joint angles, reaction force, and electromyography (EMG) from the soleus (Sol), GM, and tibialis anterior (TA) muscles were measured tog…
Disturbed motor control of rhythmic movement at 2 h and delayed after maximal eccentric actions.
2008
The aim of this study was to examine the influence of exercise-induced muscle damage on elbow rhythmic movement (RM) performance and neural activity pattern and to investigate whether this influence is joint angle specific. Ten males performed an exercise of 50 maximal eccentric elbow flexions in isokinetic machine with duty cycle of 1:15. Maximal dynamic and isometric force tests (90 degrees , 110 degrees and 130 degrees elbow angle) and both active and passive stretch reflex tests of elbow flexors were applied to the elbow joint. The intentional RM was performed in the horizontal plane at elbow angles; 60-120 degrees (SA-RM), 80-140 degrees (MA-RM) and 100-160 degrees (LA-RM). All measure…
Neuromuscular control in landing from supra-maximal dropping height.
2009
International audience; The present study utilized high-impact supra-maximal landings to examine the influence of the pre-impact force level on the post-impact electromyographic (EMG) activity and, in particular, on the short latency EMG reflex (SLR) component. Unilateral-leg landings were performed in a sitting position on a sledge apparatus after release from high, but individually constant dropping height. A lower limb guiding device fixed to the front of the sledge seat allowed the subjects to sustain a given pre-set force level up to impact. This force level was either freely chosen or set at 20, 35, and 50% of maximal isometric plantarflexion force. EMG activity was recorded from eigh…
Dominant vs. nondominant arm advantage in mentally simulated actions in right handers
2013
Although plentiful data are available regarding mental states involving the dominant-right arm, the evidence for the nondominant-left arm is sparse. Here, we investigated whether right-handers can generate accurate predictions with either the right or the left arm. Fifteen adults carried out actual and mental arm movements in two directions with varying inertial resistance (inertial anisotropy phenomenon). We recorded actual and mental movement times and used the degree of their similarity as an indicator for the accuracy of motor imagery/prediction process. We found timing correspondences (isochrony) between actual and mental right arm movements in both rightward (low inertia resistance) …
Segment coupling and coordination variability analyses of the roundhouse kick in taekwondo relative to the initial stance position.
2016
The initial stance position (ISP) has been observed as a factor affecting the execution technique during taekwondo kicks. In the present study, authors aimed to analyse a roundhouse kick to the chest by measuring movement coordination and the variability of coordination and comparing this across the different ISP (0°, 45° and 90°). Eight experienced taekwondo athletes performed consecutive kicking trials in random order from every of the three relative positions. The execution was divided into three phases (stance, first swing and second swing phase). A motion capture system was used to measure athletes' angular displacement of pelvis and thigh. A modified vector coding technique was used t…
Visual gravity influences arm movement planning.
2012
International audience; When submitted to a visuomotor rotation, subjects show rapid adaptation of visually guided arm reaching movements, indicated by a progressive reduction in reaching errors. In this study, we wanted to make a step forward by investigating to what extent this adaptation also implies changes into the motor plan. Up to now, classical visuomotor rotation paradigms have been performed on the horizontal plane, where the reaching motor plan in general requires the same kinematics (i.e., straight path and symmetric velocity profile). To overcome this limitation, we considered vertical and horizontal movement directions requiring specific velocity profiles. This way, a change i…
Analysis of sleep EEG microstructure in subchronic paroxetine treatment of healthy subjects
1997
Paroxetine is a selective and potent serotonin reuptake inhibitor and its efficacy for the treatment of depression has been proven. Under acute and subchronical treatment regimens, disturbances of the regular sleep pattern are a reported side effect of the drug. The present study was therefore performed to investigate the impact of subchronic treatment with the selective serotonin reuptake inhibitor paroxetine on the microstructure of the sleep EEG. The study especially addressed the question of subchronic effects of paroxetine medication (30 mg/day) in eight healthy male volunteers in a double blind, placebo-controlled crossover design. Conventional sleep EEG parameters and a spectral powe…
Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans
2002
Unilateral long-lasting vibration was applied to the sternomastoid muscle to assess the influence of asymmetric neck proprioceptive input on body orientation during stepping-in-place. Blindfolded subjects performed 3 sequences of 3 trials, each lasting 60 s: control, vibration applied during stepping (VDS), and vibration applied before stepping (VBS). VDS caused clear-cut whole body rotation toward the side opposite to vibration. The body rotated around a vertical axis placed at about arm's length from the body. The rotation did not begin immediately on switching on the vibrator. The delay varied from subject to subject from a few seconds to about 10 s. Once initiated, the angular velocity…
Sleep investigations in erectile dysfunction
2003
Abstract Regarding the aetiology of erectile dysfunction, beside numerous organic causes in many cases psychological factors play an important role. The pathophysiological mechanisms underlying the so-called psychogenic erectile dysfunction are not yet understood. Based on a neurobiological approach to psychogenic erectile dysfunction, polysomnographic investigations were carried out with the aim of identifying possible alterations of the sleep EEG. 24 male patients with psychogenic erectile dysfunction without detectable organic factors or other mental disorders were studied in the sleep laboratory, as well as an age-matched control group without sexual dysfunctions. Beside a reduction of …
Sleep phenotypes of intellectual disability: a polysomnographic evaluation in subjects with Down syndrome and Fragile X syndrome
2008
Abstract Objective To analyze sleep architecture and NREM sleep alterations by means of the Cyclic Alternating Pattern (CAP) in children with Down syndrome (DS) and Fragile-X syndrome (fraX), the two most common causes of inherited mental retardation, in order to find out eventual alterations of their sleep microstructure related to their mental retardation phenotypes. Methods Fourteen patients affected by fraX (mean age 13.1 years) and 9 affected by Down syndrome (mean age 13.8 years) and 26 age-matched normal controls were included. All subjects underwent overnight polysomnography in the sleep laboratory, after one adaptation night and their sleep architecture and CAP were visually scored…