caa a22 4500 445354151 CHVBK 20180317142854.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s00221-010-2465-2 doi (NATIONALLICENCE)springer-10.1007/s00221-010-2465-2 Wrist muscle activation, interaction torque and mechanical properties in unskilled throws of different speeds [Elektronische Daten] [Derek Debicki, Paul Gribble, Sherry Watts, Jon Hore] An unexpected property of unskilled overarm throws is that wrist flexion velocity at ball release does not increase in throws of increasing speed. We investigated the nature of the interaction torques and wrist mechanical properties that have been proposed to produce this property. Twelve recreational throwers made seated 2-D throws, which were used as a model for unskilled throwing. Joint motions were computed from recordings made with search coils; joint torques were calculated from inverse dynamics. Wrist flexion velocity at ball release was actually smaller in fast throws than in slow throws. This was associated in fast throws with the decrease in a large wrist flexor muscle torque (i.e., a calculated residual torque) in the last 40ms before ball release, and its reversal to an extensor torque. Consequently, wrist flexor muscle torque was unable to oppose a small maintained wrist extensor interaction torque that arose from continuing elbow extension acceleration. The decrease in wrist flexor muscle torque was not associated with a decrease in wrist flexor EMG activity, nor with an increase in wrist extensor EMG activity. These findings support the hypothesis that the smaller wrist flexion velocity at ball release in fast 2-D throws results from a wrist extensor interaction torque and from a large wrist extensor viscoelastic torque. We propose that in fast 3-D throws skilled subjects decelerate elbow extension before ball release to help overcome these wrist extensor torques. Springer-Verlag, 2010 Throwing nationallicence Interaction torque nationallicence Viscoelastic nationallicence Wrist nationallicence Human nationallicence Speed nationallicence Debicki Derek Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut Gribble Paul Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut Watts Sherry Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut Hore Jon Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut Experimental Brain Research Springer-Verlag 208/1(2011-01-01), 115-125 0014-4819 208:1<115 2011 208 221 https://doi.org/10.1007/s00221-010-2465-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00221-010-2465-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Debicki Derek Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut NATIONALLICENCE 700 1- Gribble Paul Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut NATIONALLICENCE 700 1- Watts Sherry Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut NATIONALLICENCE 700 1- Hore Jon Department of Physiology and Pharmacology, Medical Science Bldg., University of Western Ontario, N6A 5C1, London, ON, Canada aut NATIONALLICENCE 773 0- Experimental Brain Research Springer-Verlag 208/1(2011-01-01), 115-125 0014-4819 208:1<115 2011 208 221 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer