Search results for " Muscle"
showing 10 items of 1495 documents
NEUROMUSCULAR PERFORMANCE CHARACTERISTICS OF OPEN-WHEEL AND RALLY DRIVERS
2005
The purpose of the present study was to investigate neuromuscular performance characteristics in open-wheel and rally drivers using the cross-sectional study design. The subjects (N = 28) consisted of experienced international-level open-wheel drivers (n = 9), experienced international-level rally drivers (n = 9) and a physically active nondriving male control group (n = 10). In 3 separate test sessions, speed, muscle strength, and endurance tests were performed. The rally drivers had higher (p < 0.05) grip, shoulder flexion, and ankle plantar flexion strength, as compared to the control group. The open-wheel drivers showed higher strengths (p < 0.05) than the controls in neck forces, grip,…
Calf Blood Compound (CFC) and Homeopathic Drug Induce Differentiation of Primary Human Skeletal Muscle Cells.
2019
AbstractThe use of injections to treat structural muscle injuries is controversially discussed. In our controlled in vitro study, we investigated the biological impact of Actovegin and Traumeel alone and in combination on primary human skeletal muscle cells. Cells were characterized by immunofluorescence staining for myogenic factor 5 (Myf5) and MyoD, and cultured with or without Actovegin and / or Traumeel. The effects of these agents were assayed by cell viability and gene expression of the specific markers MyoD, Myf5, neural adhesion molecule (NCAM), and CD31. Myotube formation was determined by myosin staining. Neither Actovegin nor Traumeel showed toxic effects or influenced cell viabi…
Axial loading and posture cues in contraction of transversus abdominis and multifidus with exercise
2020
AbstractAstronauts are at increased risk of spine injury. With a view to developing training approaches for the muscles of the spine in microgravity, this study examined the effects of axial loading and postural cues on the contraction of transversus abdominis and lumbar multifidus in supine lying using a novel exercise device (GravityFit). Thirty (18 males and 12 females) endurance-trained runners without a history of spinal pain aged 33–55 years were recruited. Magnetic resonance imaging (MRI) was performed under one rest and five exercise conditions, which involved variations in axial loading and postural cues. Whole volume of the abdominal and lumbar paraspinal muscles was imaged and tr…
Electromyographic activity of the jaw muscles and mandibular kinematics in young adults with theoretically ideal dental occlusion: Reference values
2016
Background A necessary step to use neuromuscular analysis as diagnostic tool is to establish normal reference values for the physiological range in a healthy population. Surface electromyographic (sEMG) activity of the jaw muscles and mandibular kinematics were measured in young adults with theoretically ideal dental occlusion to determine normal reference values during different tasks. Differences between the sexes were evaluated. Material and Methods Forty young adults (20 men, 20 women; mean age 22.8 ± 3.9 years) with theoretically ideal dental occlusion were selected using very restrictive criteria. sEMG activity of the anterior temporalis (AT), posterior temporalis, masseter (MA), and …
Changes of electrically elicited reflexes in hand and forearm muscles in man.
1987
Cutaneo-muscular reflexes with short and long latency excitatory phases following digital nerve stimulation were observed in the first dorsal interosseus muscle of the hand in healthy subjects. The short latency reflex was obtained also with the H-reflex method in the flexor carpi radialis muscle, stimulating the median nerve, with a mean latency (+/- SE) of 15.4 +/- 0.5 ms. The height of the subject correlated with the H-reflex latency. The amplitudes of maximal M-response and maximal H-reflex were higher in athletes than in normals. During weak voluntary contraction of the muscle studied the 50% H-reflex amplitude increased and during passive stretching of wrist flexors the resting amplit…
Evidence of a preprogrammed deactivation of the hamstring muscles for triggering rapid changes of posture in humans
1997
Normal subjects were asked to make rapid flexions of the legs from a stationary initial standing posture in a self-paced mode. Because this movement implicates a rapid change in posture, questions were asked about the type of central command which must include the rupture of the erect posture and the accomplishment of the goal directed movement. Movements of the different segments of the body were recorded and analyzed using the optoelectronic ELITE system. Electromyographic (EMG) activities of 8 muscles of the lower limb on one side were recorded, rectified and integrated. The time relationships of the different EMG signals (activation or deactivation) were analyzed with respect to selecte…
Histological findings in direct inguinal hernia
2013
Abstract BACKGROUND: The study is focused on recognizing the histological changes of the structures close to and around the hernia opening in patients having direct inguinal hernia. METHODS: In 15 patients with primary bilateral direct inguinal hernia who underwent a Stoppa open posterior inguinal hernia repair, tissue specimens from the abdominal wall surrounding a direct hernia border were excised for histological examination. These findings in patients with direct inguinal hernia were compared with tissue specimens excised from the fossa inguinalis media of cadavers without hernia. RESULTS: Significant degenerative modifications such as fibrohyaline degeneration and fatty substitution of…
Positive inotropic response to 5-HT in human atrial but not in ventricular heart muscle
1992
The effects of 5-hydroxytryptamine (5-HT) on force of contraction (FC), action potential (AP) and calcium current (ICa) were studied in human right atrial and left ventricular heart muscle. 5-HT exerted a concentration-dependent increase in FC in multicellular atrial preparations; the EC50 was approximately 3 x 10(-7) mol/l. Maximal increases in FC (252 +/- 58% of control values; mean +/- SEM, n = 6) were obtained at 5-HT 10(-5) mol/l. At this concentration, ICa was increased four- to sevenfold in enzymatically isolated atrial myocytes. In contrast, ventricular preparations did not respond to 5-HT; FC, AP and ICa remained unaffected. In the same preparations, FC was increased by isoprenalin…
Intracortical inhibition and facilitation in human facial motor area: difference between upper and lower facial area.
2001
Objective: To investigate the intracortical inhibitory and excitatory systems in the motor cortical representation of upper and lower facial muscles. Methods: Paired-pulse transcranial magnetic stimulation (TMS) was applied to 7 healthy volunteers, with the interstimulus interval (ISI) between the conditioning stimulus (CS) and test stimulus, varied from 1 to 20 ms. CS was set at 90% of motor threshold. Muscle evoked potentials (MEPs) were recorded from first dorsal interosseus (FDI), orbicularis oculi (o. oculi) and mentalis muscles. Result: TMS evoked MEPs in o. oculi on both ipsi- and contralateral sides in all subjects. In the paired-pulse study, MEP amplitude in the mentalis decreased …