Search results for "ELECTROMYOGRAPHY"
showing 10 items of 672 documents
Leg and joint stiffness in human hopping
2010
The present study investigated the regulation of leg and joint stiffness in hopping at different intensity levels. Eight male subjects performed bilateral hopping at various intensity levels that were determined by peak vertical ground reaction force (GRF). In addition to the GRF, the measurements included hopping kinematics and electromyography (EMG) of selected leg muscles. While the leg and ankle joint stiffness remained invariant, the knee joint stiffness increased significantly (P<0.01) with the hopping intensity. EMG analysis revealed a significant increase in averaged EMG for all the measured muscles before and during the early phase of ground contact (P<0.05-0.001) with increasing h…
Influence of Aerobic Exercise After Static Stretching on Flexibility and Strength in Plantar Flexor Muscles
2020
Aerobic exercise could improve stretch-induced strength deficits. However, mechanisms of the improvement were unclear. The purpose of the study was to examine the effects of aerobic exercise after static stretching (SS) on flexibility and isometric strength in ankle plantar-flexor muscles. Fifteen healthy males received two interventions after SS of their ankle plantar-flexor muscles for 5 min. One was aerobic exercise for 10-min on a cycling ergometer, and the other was a 10-min rest as a control. Range of motion (ROM) of ankle dorsiflexion, passive torque at terminal ROM, muscle-tendon unit (MTU) stiffness, muscle tendon junction displacement, peak torque of ankle plantarflexion, and the …
Spinal and supraspinal mechanisms affecting torque development at different joint angles
2015
INTRODUCTION We examined the neural mechanisms responsible for plantar flexion torque changes at different joint positions. METHODS Nine subjects performed maximal voluntary contractions (MVC) at 6 ankle-knee angle combinations [3 ankle angles (dorsiflexion, anatomic position, plantar flexion) and 2 knee angles (flexion, full extension)]. Neural mechanisms were determined by V-wave, H-reflex (at rest and during MVC), and electromyography during MVC (RMS), normalized to the muscle compound action potential (V/Msup, Hmax/Mmax, Hsup Msup and RMS/Msup) and voluntary activation (VA), while muscle function was assessed by doublet amplitude. RESULTS MVC and doublet amplitude were significantly low…
Immune-mediated rippling muscle disease with myasthenia gravis: a report of seven patients with long-term follow-up in two.
2009
We report seven patients with immune-mediated rippling muscle disease (iRMD) and AChR-antibody positive myasthenia gravis (MG) without germline caveolin-3 gene mutations. We describe the follow-up of two patients and the clinical features of five new patients (1 female, 4 male, aged 32 to 69 years). These presented with significant generalized, exercise-induced and electrically-silent muscle rippling with myalgia, combined with generalized MG. In two of the seven patients, MG appeared before iRMD. Mediastinal imaging excluded thymic alterations in all, although two had other coincident tumours. Myalgia and rippling were aggravated by acetylcholinesterase-inhibitor treatment. Generalized MG …
Myoadenylate deaminase deficiency
1987
Myoadenylate deaminase (MAD) is the rate-limiting enzyme in the purine nucleotide cycle which is biochemically linked to glycolysis and the citric cycle and thereby providing energy during intense muscular activity. In muscle fibers, myoadenylate deaminase operates at considerably higher activity levels than in other organs. First detected using enzyme-histochemical methods, it now appears that deficiency of myoadenylate deaminase is one of the most frequent enzyme defects in muscle. The primary defect may occur as an isolated nosological entity or not infrequently it is also associated with a large spectrum of different neuromuscular conditions. It seems to be the primary unassociated MAD …
Effects of Upper Body Eccentric versus Concentric Strength Training and Detraining on Maximal Force, Muscle Activation, Hypertrophy and Serum Hormone…
2022
Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were mea…
Wpływ stanu napięcia mięśni dna miednicy na ocenę poziomu zaburzeń erekcji i nietrzymania moczu u osób po prostatektomii radykalnej. Doniesienie wstę…
2017
Celem pracy była ocena, jak napięcie mięśni dna miednicy (MDM) mierzonego za pomocą sEMG wpływa na ocenę obiektywną i subiektywną trzymania moczu oraz zaburzeń erekcji. W badaniach uczestniczyło 10 mężczyzn, będących po zabiegu prostatektomii. Nasilenie objawów nietrzymania moczu oceniano na podstawie kwestionariusza ICIQ-SF, aktywność seksualną kwestionariuszem IIEF-5. Nie wykazano istotnego statystycznie związku między napięciem MDM, ocenianego za pomocą sEMG, a obiektywnymi wyznacznikami nietrzymania moczu, jednakże zaobserwowano tendencję, że niższe napięcie MDM występuje częściej u chorych ze wszystkimi dolegliwościami w ocenie subiektywnej.
Functional adaptation of sarcolemma to physical stress
2010
Modulations of corticospinal excitability following rapid ankle dorsiflexion in skill- and endurance-trained athletes
2022
Abstract Purpose Long-term sports training, such as skill and endurance training, leads to specific neuroplasticity. However, it remains unclear if muscle stretch-induced proprioceptive feedback influences corticospinal facilitation/inhibition differently between skill- and endurance-trained athletes. This study investigated modulation of corticospinal excitability following rapid ankle dorsiflexion between well-trained skill and endurance athletes. Methods Ten skill- and ten endurance-trained athletes participated in the study. Corticospinal excitability was tested by single- and paired-pulse transcranial magnetic stimulations (TMS) at three different latencies following passive rapid ankl…