Neuromuscular control mechanisms and strategy in arm movements of attempted supranormal speed.
Rapid, goal-directed elbow flexion movements were examined under interacting conditions of inertial loading and resistance to movement initiation. The resistance ceased when movement began, resulting in quick release movements. Inertial load slowed the movement and lengthened the agonist and antagonist electromyographic (EMG) burst durations. The quick release resulted in larger accelerations but only minimal changes in peak velocity. Most aspects of the triphasic EMG pattern were little affected by the quick release, but the build up of agonist EMG and the corresponding rate of static force development differed markedly between load and quick release conditions. These and other data suggest that the specific pattern of agonist muscle activation is set according to neuromuscular constraints of the antagonist muscle and the expectation of movement dynamics.
Ives
J C
JC
Department of Exercise and Sport Sciences, Ithaca College, USA. jives@ithaca.edu
Abraham
L
L
Kroll
W
W
D000054:Acceleration; D000328:Adult; D000704:Analysis of Variance; D001132:Arm / Q000502:physiology*; D001696:Biomechanical Phenomena; D004551:Elbow Joint / Q000502:physiology; D004576:Electromyography; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D009068:Movement; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D009469:Neuromuscular Junction / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D011930:Reaction Time; D012044:Regression Analysis; D016474:Weight-Bearing / Q000502:physiology