Search results for "Excentrique"
showing 4 items of 4 documents
Influence of the muscle mode of contraction on the exercise induced neuroplastic effects
2018
Along with cardiovascular and neuromuscular changes, mono-articular and locomotor exercises may induced neuroplastic changes from muscles involved, or non-involved, in the exercise. If the effect of exercise intensity or duration on neuroplastic changes has been previously investigated, the effect of the mode of muscle contraction remains unclear. The aim of this thesis was to investigate the effects of the mode of muscle contraction on neuroplastic changes induced a locomotor or a single-joint exercise. The first study showed that the increase in the corticospinal excitability of a non-exercised hand muscle, observed after a walking/ running exercise, was not modulated by the knee extensor…
Altérations neuromusculaires induites par des exercices excentriques et concentriques fatigants : emphase sur le pédalage des membres inférieurs
2021
The influence of dynamic contraction type (concentric or eccentric) on performance fatigability and associated neuromuscular alterations is partly unknown. Contraction type interacts with other exercise features such as intensity (maximal; submaximal) or modality (single-joint; locomotor). Thus, we compared eccentric with concentric exercises of similar characteristics across three experimental studies. We showed that, for the completion of a given amount of mechanical work, both contraction types impaired maximal voluntary isometric torque similarly. However, neuromuscular impairments depended on exercise features. In study 1, maximal single-joint eccentric contractions affected neural but…
Dépendance de la fatigue à la longueur musculaire : approche mécanique et neurophysiologique
2006
The objective of this work is to evaluate the fatigue dependency on the knee extensor muscles length. Exercises varying the type of contraction (isometric and eccentric) and intensity of contraction (maximal and sub-maximal) are performed in order to disrupt the neuromuscular system by different factors of fatigue: central and peripheral. These exercises are performed at two muscular lengths (S and L, corresponding respectively to 40 and 100° of knee flexion). Neuromuscular parameters (maximal torque, muscular twitch, voluntary activation level, electromyographic activity, etc.) are analyzed in pre- and post-fatigue conditions in the type of contraction required by the fatiguing exercise. I…
Altération des performances neuromusculaires après un exercice physique prolongé. Analyse comparée d'une épreuve de marathon et de triathlon
1998
The aim of this study was to compare the effects of a marathon and a triathlon on isometric and dynamic neuromuscular performances. Seven triathletes took part in 3 experimental situations : a 2 h 15 mn triathlon (TRI) (30 min swimming, 60 min cycling and 45 min running), a 2 h 15 mn marathon (MA) and a 45 min isolated run done at triathlon speed. The results showed a reduction of the isometric endurance time for knee extensor muscles (35 % of maximal voluntary contraction) after TRI (41 ± 24 %) and after MA (59 ± 19 %). The height of rise of the center of gravity of the counter-movement jumps (CMJ) was also significantly lower after MA (-12 ± 1 cm) than after TRI (-2,5 0,5 cm). Kinetic ana…