Browsing by Author "Hortobágyi, Tibor"
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Changes in muscle strength, muscle fibre size and myofibrillar gene expression after immobilization and retraining in humans
Hortobágyi, Tibor; Dempsey, G. Lynis; Fraser, D. D.; Zheng, D.; Hamilton, G.; Lambert, J.; Dohm, G. Lynis (East Carolina University, 2000-01)1. Changes in muscle strength, vastus lateralis fibre characteristics and myosin heavychain (MyoHC) gene expression were examined in 48 men and women following 3 weeks of knee immobilization and after 12 weeks of retraining ... -
Chronic low-frequency rTMS of primary motor cortex diminishes exercise training-induced gains in maximal voluntary force in humans
Hortobágyi, Tibor; Richardson, Sarah Pirio; Lomarev, Mikhael; Shamim, Ejaz; Meunier, Sabine; Russman, Heike; Dang, Nguyet; Hallett, Mark (East Carolina University, 2009)Although there is consensus that the central nervous system mediates the increases in maximal voluntary force (maximal voluntary contraction, MVC) produced by resistance exercise, the involvement of the primary motor cortex ... -
A Comparison of Lean and Obese Gait Characteristics of Children and Adults During Level Walking
Herring, Cortney S. (East Carolina University, 2010)Increased body mass affects gait kinematics and kinetics in adults. It is however unknown if increased body mass produces similar adaptations in children and adults. The duration of obesity in children is shorter than ... -
How do low horizontal forces produce disproportionately high torques in human locomotion?
Helseth, Joseph; Hortobágyi, Tibor; DeVita, Paul, 1955- (East Carolina University, 2008)Although horizontal ground forces are only ~15% of vertical forces, they account for 47% and 33% of the metabolic cost in walking and running. To explain these disproportionately high metabolic costs we hypothesized that ... -
Incorporating a visuomotor skill task with resistance training does not increase strength gains in healthy young adults
Morgan, Jeff (East Carolina University, 2012)Resistance training causes well-documented adaptations in the nervous system and increases maximal voluntary force of healthy human skeletal muscle in the trained and also of the same muscle in untrained limb. It is also ... -
Increased Antagonist Coactivation-Related Hamstring Torque Reduces Maximal Knee Extension Torque in Healthy Old Adults
Gomez, Jonathan R. (East Carolina University, 2010)As humans age, the ability to produce maximal voluntary torque decreases due to muscle atrophy (sarcopenia) and it is also known that advancing age alters the neural control of voluntary movement. One manifestation of the ... -
Influence of training history and contraction velocity on hamstring muscle coactivation during maximal effort knee extension
Brady, Robert B. (East Carolina University, 2012)When a muscle produces voluntary force, muscles on the opposite side of the joint, the antagonists, are also activated. While coactivation of the knee flexors during knee extension is presumed to increase joint stability ... -
The Interaction of Trunk-Load and Trunk-Position Adaptations on Knee Anterior Shear and Hamstrings Muscle Forces During Landing
Kulas, Anthony S.; Hortobágyi, Tibor; DeVita, Paul, 1955- (East Carolina University, 2010)Context: Because anterior cruciate ligament (ACL) injuries can occur during deceleration maneuvers, biomechanics research has been focused on the lower extremity kinetic chain. Trunk mass and changes in trunk position ... -
Modulation of H Reflex in Response to Voluntary Contraction of the Homologous Muscle in the Contralateral Limb
Motawar, Binal (East Carolina University, 2010)Several studies reported that exercising one limb produces gains in motor output in the same muscle of the un-exercised, contralateral limb. This phenomenon is called cross education. There are also data to suggest that ... -
Muscle work is biased toward energy generation over dissipation in non-level running
DeVita, Paul, 1955-; Janshen, Lars; Rider, Patrick; Solnik, Stanislaw; Hortobágyi, Tibor (East Carolina University, 2008-12-05)This study tested the hypothesis that skeletal muscles generate more mechanical energy in gait tasks that raise the center of mass compared to the mechanical energy they dissipate in gait tasks that lower the center of ... -
Muscles do more positive than negative work in human locomotion
DeVita, Paul, 1955-; Helseth, Joseph; Hortobágyi, Tibor (East Carolina University, 2007-10)Muscle work during level walking and ascent and descent ramp and stairway walking was assessed in order to explore the proposition that muscles perform more positive than negative work during these locomotion tasks. Thirty ... -
NEURAL MECHANISMS CONTRIBUTE TO THE AGE RELATED INCREASE IN METABOLIC COST OF GAIT
Finch, Adria D. (East Carolina University, 2010)Aging is associated with biomechanical and physiological changes in several organ systems, including neural changes of voluntary movement. One manifestation of age-related changes in neural control of gait is the increased ... -
Task Specific Effects of Unilateral Eccentric and Concentric Exercise on Spinal Excitability of the Contralateral Homologous Plantar Flexors.
Hill, Ryan D. (East Carolina University, 2011)It is well established that resistance training increases the size and strength of the trained muscles. It is also known that unilateral muscle contractions can produce strength gains in the non-exercised contralateral ... -
Teager-Kaiser Operator improves the accuracy of EMG onset detection independent of signal-to-noise ratio
Solnik, Stanislaw; DeVita, Paul, 1955-; Rider, Patrick; Long, Benjamin L.; Hortobágyi, Tibor (East Carolina University, 2008)A temporal analysis of electromyographic (EMG) activity has widely been used for non-invasive study of muscle activation patterns. Such an analysis requires robust methods to accurately detect EMG onset. We examined whether ... -
Teager–Kaiser energy operator signal conditioning improves EMG onset detection
Solnik, Stanislaw; Rider, Patrick; Steinweg, Ken; DeVita, Paul, 1955-; Hortobágyi, Tibor (2010-06)