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"Velocity" "muscle architecture" "dynamic"

Jacobo Ángel Rubio-Arias, Domingo Jesús Ramos-Campo, Paula Esteban, Fernando Martínez, José Fernando Jiménez
The purpose of the current study was to examine the effect of 6 weeks of whole body vibration training (WBVT) on body composition, muscle activity of the gastrocnemius and vastus lateralis, gastrocnemius muscle architecture (static and dynamic) and ground reaction forces (performance jump) during the take-off phase of a countermovement jump in young healthy adult males. A total of 33 men (23.31 ± 5.62 years) were randomly assigned to a whole body vibration group (experimental group, EGWBVT: n = 17; 22...
April 5, 2017: Journal of Sports Sciences
Jacobo Ángel Rubio-Arias, Domingo Jesús Ramos-Campo, José Peña Amaro, Paula Esteban, Susana Mendizábal, José Fernando Jiménez
PURPOSE: The purpose of this study was to analyse gender differences in neuromuscular behaviour of the gastrocnemius and vastus lateralis during the take-off phase of a countermovement jump (CMJ), using direct measures (ground reaction forces, muscle activity and dynamic ultrasound). METHODS: Sixty-four young adults (aged 18-25 years) participated voluntarily in this study, 35 men and 29 women. The firing of the trigger allowed obtainment of data collection vertical ground reaction forces (GRF), surface electromyography activity (sEMG) and dynamic ultrasound gastrocnemius of both legs...
November 2017: Clinical Physiology and Functional Imaging
Juliano Spineti, Tiago Figueiredo, Viviane Bastos DE Oliveira, Marcio Assis, Liliam Fernandes DE Oliveira, Humberto Miranda, Victor M Machado DE Ribeiro Reis, Roberto Simão
BACKGROUND: The purpose of this study was to compare traditional strength training (TST) and complex contrast training (CCT) on the repeated-shuttle-sprint ability (RSSA), the countermovement squat jump (CMJ) height, the one repetition maximum (1RM) at squat on the Smith machine, and on muscle architecture in young, male elite soccer players. METHODS: Twenty-two soccer players (mean age 18.4±0.4 years; mean weight 70.2±9.1 kg; mean height 179.9±7.5 cm) who belonged to the under-20 age group were randomly assigned into two groups: CCT (N...
November 2016: Journal of Sports Medicine and Physical Fitness
T Martín Lorenzo, S Lerma Lara, I Martínez-Caballero, E Rocon
Evaluation of muscle structure gives us a better understanding of how muscles contribute to force generation which is significantly altered in children with cerebral palsy (CP). While most muscle structure parameters have shown to be significantly correlated to different expressions of strength development in children with CP and typically developing (TD) children, conflicting results are found for muscle fascicle length. Muscle fascicle length determines muscle excursion and velocity, and contrary to what might be expected, correlations of fascicle length to rate of force development have not been found for children with CP...
October 2015: Medical Hypotheses
Tobias Siebert, Kay Leichsenring, Christian Rode, Carolin Wick, Norman Stutzig, Harald Schubert, Reinhard Blickhan, Markus Böl
The vastly increasing number of neuro-muscular simulation studies (with increasing numbers of muscles used per simulation) is in sharp contrast to a narrow database of necessary muscle parameters. Simulation results depend heavily on rough parameter estimates often obtained by scaling of one muscle parameter set. However, in vivo muscles differ in their individual properties and architecture. Here we provide a comprehensive dataset of dynamic (n = 6 per muscle) and geometric (three-dimensional architecture, n = 3 per muscle) muscle properties of the rabbit calf muscles gastrocnemius, plantaris, and soleus...
2015: PloS One
Andrew A Biewener, James M Wakeling, Sabrina S Lee, Allison S Arnold
We review here the use and reliability of Hill-type muscle models to predict muscle performance under varying conditions, ranging from in situ production of isometric force to in vivo dynamics of muscle length change and force in response to activation. Muscle models are frequently used in musculoskeletal simulations of movement, particularly when applied to studies of human motor performance in which surgically implanted transducers have limited use. Musculoskeletal simulations of different animal species also are being developed to evaluate comparative and evolutionary aspects of locomotor performance...
December 2014: Integrative and Comparative Biology
Edith M Arnold, Samuel R Hamner, Ajay Seth, Matthew Millard, Scott L Delp
The lengths and velocities of muscle fibers have a dramatic effect on muscle force generation. It is unknown, however, whether the lengths and velocities of lower limb muscle fibers substantially affect the ability of muscles to generate force during walking and running. We examined this issue by developing simulations of muscle-tendon dynamics to calculate the lengths and velocities of muscle fibers from electromyographic recordings of 11 lower limb muscles and kinematic measurements of the hip, knee and ankle made as five subjects walked at speeds of 1...
June 1, 2013: Journal of Experimental Biology
Gianpiero De Monte, Adamantios Arampatzis
The purpose of this study was to examine the influence of different shortening velocities preceding the stretch on moment generation of the triceps surae muscles and architecture of the m. gastrocnemius medialis after shortening-stretch cycles of equal magnitude in vivo. Eleven male subjects (31.6+/-5.8 years, 178.4+/-7.3cm, 80.6+/-9.6kg) performed a series of electro-stimulated (85Hz) shortening-stretch plantar flexion contractions. The shortening-stretch cycles were performed at three constant angular velocities (25, 50, 100 degrees /s) in the plantar flexion direction (shortening) and at 50 degrees /s in the dorsiflexion direction (stretching)...
July 19, 2008: Journal of Biomechanics
Gianpiero De Monte, Adamantios Arampatzis
The purpose of this study was to examine the moment generation of the human plantar flexors and the architecture of the gastrocnemius medialis muscle during and after shortening-stretch cycles in vivo. Fourteen male subjects (30+/-7 years, 177+/-7 cm, 80+/-9 kg) performed a series of electro-stimulated shortening-stretch plantar flexion contractions. The shortening-stretch cycles were performed at three constant angular velocities (25 degrees /s, 50 degrees /s, 100 degrees /s), two amplitudes (15 degrees and 25 degrees ankle angle changes) and at two different stimulation frequencies (30 Hz and 85 Hz)...
April 2009: Journal of Electromyography and Kinesiology
Luis M Alegre, Fernando Jiménez, José Manuel Gonzalo-Orden, Rafael Martín-Acero, Xavier Aguado
The aims of this study were to assess changes in muscle architecture, isometric and dynamic strength of the leg extensor muscles, resulting from dynamic resistance training, and the relationships between strength and muscle architecture variables. The participants (n = 30) were randomly assigned to one of two groups. The training group (n = 16; age 21.8 +/- 2.3 years, body mass 74.8 +/- 9.2 kg, height 1.75 +/- 0.08 m) performed dynamic resistance training for 13 weeks. The control group (n = 14; age 19.9 +/- 1...
May 2006: Journal of Sports Sciences
Neil D Reeves, Constantinos N Maganaris, Marco V Narici
Data are scarce relating to the plasticity with strength training of dynamic muscle performance in older humans. Hence, we investigated alterations in the torque-velocity relation with strength training in old age, and their origin. Knee extension and leg-press exercises were performed three times per week for 14 weeks. Maximal isokinetic knee extension torque was assessed during concentric and eccentric muscle actions. Agonist-antagonist muscle activation was assessed using electromyography. Vastus lateralis muscle architecture was examined in vivo using ultrasonography...
March 2005: Muscle & Nerve
Laura Zarucco, Ken T Taylor, Susan M Stover
OBJECTIVE: To provide a quantitative description of the architecture of superficial digital flexor (SDF) and deep digital flexor (DDF) muscles in adult horses to predict muscle-tendon behavior and estimate muscle forces. SAMPLE POPULATION: 7 forelimb specimens from 7 adult Thoroughbreds. PROCEDURE: Muscle and tendon lengths and volumes were measured from 6 fixed forelimbs. After processing, fiber bundle and sarcomere lengths were measured...
June 2004: American Journal of Veterinary Research
Neil D Reeves, Marco V Narici
The aim of the present study was to investigate the behavior of human muscle fascicles during dynamic contractions. Eight subjects performed maximal isometric dorsiflexion contractions at six ankle joint angles and maximal isokinetic concentric and eccentric contractions at five angular velocities. Tibialis anterior muscle architecture was measured in vivo by use of B-mode ultrasonography. During maximal isometric contraction, fascicle length was shorter and pennation angle larger compared with values at rest (P < 0...
September 2003: Journal of Applied Physiology
T Johansson, P Meier, R Blickhan
In the present paper, a finite-element model for simulating muscle mechanics is described. Based on nonlinear continuum mechanics an algorithm is proposed that includes the contractile active and passive properties of skeletal muscle. Stress in the muscle is assumed to result from the superposition of a passive and an active part. The passive properties are described by a hyperelastic constitutive material law whereas the active part depends on the fibre length, shortening velocity and an activation function...
September 7, 2000: Journal of Theoretical Biology
A J van den Bogert, K G Gerritsen, G K Cole
Methods for developing mathematical models representing entire human muscles are briefly reviewed, with special emphasis on aspects of modelling velocity dependence using cross-bridge dynamics, and isometric force-length properties from myofilament lengths and muscle architecture. For each of these components, mechanistic (using basic contraction mechanisms) and phenomenological ("black-box") models are available. Experiments on constant-velocity lengthening at different velocities were simulated using (a) a cross-bridge based model and (b) a Hill-based model...
April 1998: Journal of Electromyography and Kinesiology
S A Spector, P F Gardiner, R F Zernicke, R R Roy, V R Edgerton
1. Isometric and isotonic contractile parameters of the soleus (SOL) and medial gastrocnemius (MG) muscles of seven adult cats were studied. In addition, architectural characteristics of six contralateral pairs of these ankle extensors were determined. 2. The in situ peak isometric tetanic tension developed by the MG at the Achilles tendon is nearly 5 times (9,846 vs 2,125 g) that of the SOL muscle. However, when differences between the MG and SOL in fiber length (2.01 vs 3.66 cm), muscle mass (9.80 vs. 3.31 g), and angle of pinnation (21...
November 1980: Journal of Neurophysiology
S S Segal, T P White, J A Faulkner
Skeletal muscle grafts have a deficit in tension development compared with control muscles, even after accounting for reduced mass and total muscle cross-sectional area. Our purpose was to determine relationships among the architecture, tissue composition, and contractile properties of rat soleus muscle grafts. Data were compared with control soleus muscles obtained from littermates. Female Wistar rats were anesthetized with pentobarbital sodium for grafting of soleus muscles with nerve implant and for dissection of muscles 56 days after grafting...
March 1986: American Journal of Physiology
K R Kaufman, K W An, W J Litchy, E Y Chao
A physiological model for predicting muscle forces is described. Rigid-body mechanics and musculoskeletal physiology are used to describe the dynamics of the segment model and muscle model. Unknown muscle and joint contact forces outnumber the equilibrium equations resulting in an indeterminate problem. Mathematical optimization is utilized to resolve the indeterminacy. The modeling procedure relies entirely on established physiological principles. Data describing the muscle anatomy and body structures are included...
1991: Neuroscience
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