Search results for "stretch"
showing 10 items of 170 documents
Spectroscopic markers of the T-R quaternary transition in human hemoglobin
2004
n questo lavoro, usiamo un protocollo sol-gel per intrappolare e confrontare gli stati quaternari R e T di entrambi i deossigenati (deossiHb) ederivati di ossido di carbonio (HbCO) dell'emoglobina umana. La banda di assorbimento ottico del vicino infrarosso III e lo stretching di CO a infrarossibanda sono utilizzati per rilevare l'effetto della struttura quaternaria sulle proprietà spettrali di deoxyHb e HbCO; confronto con mioglobinaconsente una valutazione dei contributi terziari e quaternari ai turni di banda misurati. La RXLa transizione T è indicata per causare un bluspostamento della banda III di ~ 35 cm?1per deoxyHb e uno spostamento rosso della banda di allungamento CO di soli ~ 0…
Influence of the early bacterial biofilms developed on vats made with seven wood types on PDO Vastedda della valle del Belìce cheese characteristics
2019
Early vat bacterial biofilms developed spontaneously through contact with whey have been characterized on seven wood types (Castanea sativa Miller, Cedrus libani, A. Rich., Prunus avium L., Fraxinus ornus L., Juglans regia L., Pinus nigra J.F. Arnold and Populus nigra L.). The present study aimed to evaluate the influence of these biofilms on the microbiological, chemical, physical and sensory characteristics of PDO Vastedda della valle del Belìce (VdB) cheese, processed traditionally from raw ewe's milk using wooden tools. To this purpose, the experimental cheeses after 15 d of refrigerated storage were examined. Lactic acid bacteria (LAB) populations dominated the microbial community of a…
Bimodal Recovery Pattern in Human Skeletal Muscle Induced by Exhaustive Stretch-Shortening Cycle Exercise:
2007
Introduction/Purpose: Recovery of force and stretch reflex from exhaustive stretch-shortening cycle (SSC) exercise is usually bimodal, characterized as immediate exercise-induced performance reduction, with its quick recovery followed by a longer-lasting reduction in performance. A clear parallel exists between the respective changes in performance, neural activation, and metabolic or structural exercise-induced changes. This implies the existence of potential coupling between muscle failure and the induced neural adjustments that take place along its recovery. The present study was designed to explore the evidence of this coupling more thoroughly. Methods: H- and stretch reflexes were meas…
Acute effects of 15min static or contract-relax stretching modalities on plantar flexors neuromuscular properties
2010
The present study aimed to investigate the immediate effects of 15 min static or sub-maximal contract-relax stretching modalities on the neuromuscular properties of plantar flexor muscles. Ten male volunteers were tested before and immediately after 15 min static or contract-relax stretching programs of plantar flexor muscles (20 stretches). Static stretching consisted in 30s stretches to the point of discomfort. For the contract-relax stretching modality, subjects performed 6s sub-maximal isometric plantar flexion before 24s static stretches. Measurements included maximal voluntary isometric torque (MVT) and the corresponding electromyographic activity of soleus (SOL) and medial gastrocnem…
Genetic variation in neuromuscular performance.
1973
Using a simple cumulative model of heredity plus environment, based on intrapair differences observed in monozygous (MZ) and dizygous (DZ) twins, the relative contribution of heredity to the interindividual variance in several neuromuscular parameters was determined with 15 pairs of male (8 MZ and 7 DZ) and 14 pairs of female (7 MZ and 7 DZ) twins ranging in age from 10 to 14 years. The data disclosed that in boys the variability in maximal mechanical (anaerobic) power was 99.2% genetically determined under the environmental conditions of the study. The corresponding heritability estimate values for the patellar reflex time and reaction time were 97.5% and 85.7%, respectively. In girls the …
Impact of the Prone Position in an Animal Model of Unilateral Bacterial Pneumonia Undergoing Mechanical Ventilation
2013
Abstract Background: The prone position (PP) has proven beneficial in patients with severe lung injury subjected to mechanical ventilation (MV), especially in those with lobar involvement. We assessed the impact of PP on unilateral pneumonia in rabbits subjected to MV. Methods: After endobronchial challenge with Enterobacter aerogenes, adult rabbits were subjected to either “adverse” (peak inspiratory pressure = 30 cm H2O, zero end-expiratory pressure; n = 10) or “protective” (tidal volume = 8 ml/kg, 5 cm H2O positive end-expiratory pressure; n = 10) MV and then randomly kept supine or turned to the PP. Pneumonia was assessed 8 h later. Data are presented as median (interquartile range). Re…
Achilles tendon length changes during walking in long-term diabetes patients
2010
Diabetes leads to numerous side effects, including an increased density of collagen fibrils and thickening of the Achilles tendon. This may increase tissue stiffness and could affect stretch distribution between muscle and tendinous tissues during walking. The primary aim of this study was to examine stretch distribution between muscle and tendinous tissues in the medial gastrocnemius muscle-tendon unit in long-term diabetes patients and control subjects during walking.Achilles tendon length changes were investigated in 13 non-neuropathic diabetes patients and 12 controls, whilst walking at a self selected speed across a 10 m force platform. Electromyographic activity was recorded in the me…
Muscle strength and range of movement deficits 1 year after hip resurfacing surgery using posterior approach.
2009
The aim was to evaluate the effect of the posterior surgical approach on hip muscle strength and range of movement (ROM).Maximal isometric external and internal rotator strength of the hip muscles and bilateral leg extension strength were measured by dynamometers. Active (AROM) and passive (PROM) range of motion of the hip were measured by goniometers in 30 patients before and 3, 6 and 12 months after hip resurfacing. Postoperatively the patients were advised to return to their usual physical activities.Prior to the surgery internal rotation strength was on the same level on both sides, whereas external rotation strength of the operated hip was 26% (p0.001) lower compared with the unoperate…
Effects of Joint Kinetics on Energy Cost during Repeated Vertical Jumping
2019
The present study was designed to investigate the effects of lower limb joint kinetics on energy cost during jumping.Eight male middle and long-distance runners volunteered for the study. The subjects were asked to repeat vertical jumps at a frequency of 2 Hz for 3 min on a force platform in three different surface inclination conditions: Incline (+8°), Level (0°), and Decline (-8°). Sagittal plane kinematics were obtained using a high-speed video camera. Simultaneously, ground reaction forces and EMG of the lower limb muscles were recorded. Energy cost was calculated using steady-state oxygen uptake, respiratory ratio, and vertical distance of the body.In all conditions, energy cost correl…
Behaviour of vastus lateralis muscle-tendon during high intensity SSC exercises in vivo
2003
Aims: The interaction between fascicle and tendinous tissue of human vastus lateralis muscle was investigated during varying intensity stretch–shortening cycle (SSC) jumps performed on a sledge apparatus. Methods: Eight subjects performed single leg squat (SJ) and drop jumps (DJ) from a constant dropping height but to different rebound heights. The fascicle length of the vastus lateralis muscle (VL) was determined from real-time ultrasonography during the movement. Tendon length changes were calculated by subtracting the horizontal part of the fascicle length from the muscle–tendon unit (MTU) length. Simultaneously, kinematic, kinetic and electromyographic data were recorded from leg musc…