Search results for "Neuromuscular"
showing 10 items of 363 documents
Differential blockade by nifedipine and ω-conotoxin GVIA of α1- and β1-adrenoceptor-controlled calcium channels on motor nerve terminals of the rat
1990
Electrically evoked release of [3H]acetylcholine ([3H]ACh) from the rat phrenic nerve and its facilitation by stimulation of presynaptic alpha 1- and beta 1-adrenoceptors were investigated in the absence and presence of nifedipine and omega-conotoxin GVIA. Both calcium channel antagonists did not modify electrically evoked [3H]ACh release, but selectively blocked the effect triggered by both facilitatory adrenergic receptors. The increase in [3H]ACh release mediated via beta 1-adrenoceptor activation was abolished by low concentrations (1 nM) of omega-conotoxin GVIA, whereas nifedipine (100 nM) abolished the facilitatory effect mediated via alpha 1-adrenoceptor stimulation. Therefore, the b…
Effects of military basic training on VO2max, body composition, muscle strength and neural responses in conscripts of different aerobic condition
2019
Summary Study aim: The purpose of this study was to evaluate neuromuscular adaptations in conscripts with different fitness levels (VO2max) during 8 weeks of military basic training (BT). Material and methods: Twenty-four male conscripts (18–21 years) were divided into two groups (Good Fitness [GF] and Low fitness [LF]) based on their VO2max at the beginning of BT. Body mass (BM), fat free mass (FFM) and Fat% were measured after 2, 4, and 7 weeks of training. VO2max, maximal isometric leg press force (MVC), H-reflex (Hmax/Mmax) at rest and V-wave (V/Mmax) during maximal isometric plantarflexion were measured from the soleus muscle at the beginning, after 5, and after 8 weeks of training. Re…
Exercise and ankle sprain injuries: a comprehensive review.
2014
Ankle sprains are common in team sports and sports played on courts, and often result in structural and functional alterations that lead to a greater reinjury risk. Specific exercises are often used to promote neuromuscular improvements in the prevention and rehabilitation of ankle injuries. This literature review summarizes the neuromuscular characteristics of common ankle sprains and the effectiveness of exercise as an intervention for improving neuromuscular function and preventing reinjury. Our review found that appropriate exercise prescription can increase static and dynamic balance and decrease injury recurrence. In particular, the addition of dynamic activities in the exercise progr…
Characterization of endogenous noradrenaline release from intact and epithelium-denuded rat isolated trachea.
1991
1. Overflow of endogenous noradrenaline (NA) from the in vitro incubated rat trachea evoked by two periods of electrical field stimulation (S1, S2 at 3 or 15 Hz) or by high potassium (60 mM) was determined by high performance liquid chromatography (h.p.l.c.) with electrochemical detection. 2. In the presence of the neuronal uptake inhibitor desipramine, the alpha 2-adrenoceptor antagonist, yohimbine, enhanced the overflow of NA evoked by stimulation at 3 Hz by about 100% suggesting the presence of presynaptic inhibitory autoreceptors on the sympathetic nerves innervating the trachea. 3. When desipramine and yohimbine were present throughout the experiments, the overflow of NA evoked by the …
Neuromuscular Training Warm-up Prevents Acute Noncontact Lower Extremity Injuries in Children’s Soccer : A Cluster Randomized Controlled Trial
2021
Background: Prevention of sports injuries is essential in youth, as injuries are associated with less future physical activity and thus greater all-cause morbidity. Purpose: To investigate whether a neuromuscular training warm-up operated by team coaches is effective in preventing acute lower extremity (LE) injuries in competitive U11-U14 soccer players. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Twenty top-level U11 to U14 soccer clubs in Finland were randomized into intervention and control groups and assessed for 20 weeks. Participants included 1403 players (280 female, 1123 male; age range, 9-14 years): 673 players (44 teams) in the intervention group and …
Alterations of Neuromuscular Function After Prolonged Running, Cycling and Skiing Exercises
2004
It is well known that impairment of performance resulting from muscle fatigue differs according to the types of contraction involved, the muscular groups tested and the exercise duration/intensity. Depending on these variables, strength loss with fatigue can originate from several sites from the motor cortex through to contractile elements. This has been termed 'task dependency of muscle fatigue'. Only recently have studies focused on the origin of muscle fatigue after prolonged exercise lasting 30 minutes to several hours. Central fatigue has been shown to contribute to muscle fatigue during long-distance running by using different methods such as the twitch interpolation technique, the ra…
Efficacy of botulinum toxin in the treatment of bruxism : systematic review
2019
Background Currently it has been shown that botulinum toxin is effective for a wide variety of medical conditions, and can be applied for therapeutic purposes as cosmetic. In recent years, there has been a growing trend in the use of this drug substance to control the muscular overactivity of bruxism. The objective of this study was the use of botulinum toxin type A (BTX-A) than traditional methods, by conducting a systematic review of randomized clinical trials (RCTs) published in the health sciences literature. Material and Methods An electronic search was made in the databases of the PubMed, Cochrane Library and Scopus data between March and October 2017, ECA, which will analyze the effe…
Normative values for musculoskeletal- and neuromotor fitness in apparently healthy Norwegian adults and the association with obesity: a cross-section…
2016
Background Up-to-date research on musculoskeletal- and neuromotor fitness (MSMF) is lacking. The aims of the present paper were to a) establish normative values of MSMF by gender and age, and b) to assess how much of the variance in MSMF can be explained by obesity in adults. Methods A random selection of 726 Norwegians (20–65 years) participated in a national cross-sectional study. Muscular endurance, muscular strength, explosive power, flexibility and balance were assessed in addition to waist circumference (WC). Results Females displayed significantly higher scores compared to males on muscular endurance of the back extensors and on the flexibility tests (p < 0.001). Males displayed sign…
Der Effekt von Neostigmin an der motorischen Endplatte beim Intermediärsyndrom der Alkylphosphatvergiftung
1991
A patient with severe organophosphate intoxication received Neostigmine 1 mg IV during the intermediate syndrome. This dose resulted clinically and neurophysiologically in a marked deterioration of neuro-muscular transmission. This effect of neostigmine on the neuromuscular block during the intermediate syndrome (deterioration) differs from its effect on a similar pattern (improvement), which is seen in the delayed neuropathy following organophosphate exposure. The administration of therapeutic doses of cholinesterase inhibitors in patients with a reduced safety margin due to inhibition of endplate acetylcholinesterase may be dangerous.
The Stretch-Shortening Cycle
2006
Neuromuscular fatigue has traditionally been examined using isolated forms of either isometric, concentric or eccentric actions. However, none of these actions are naturally occurring in human (or animal) ground locomotion. The basic muscle function is defined as the stretch-shortening cycle (SSC), where the preactivated muscle is first stretched (eccentric action) and then followed by the shortening (concentric) action. As the SSC taxes the skeletal muscles very strongly mechanically, its influence on the reflex activation becomes apparent and very different from the isolated forms of muscle actions mentioned above. The ground contact phases of running, jumping and hopping etc. are example…