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THE IMPORTANCE OF NEGATIVE ACCELERATION OF THE LOAD IN FREE-STYLE LIFTING
Jordan Trafimow1, Joseph Xaygnaraj1, David Trafimow2
11 Department of Physical Therapy, University of Illinois at Chicago, USA.
Abstract:
Lifters may use negative acceleration in lifting a very light load. Body kinematic data were recorded in 10 participants lifting a 114 g box. Vertical position and acceleration of the center of mass and angle of the thigh to a vertical line were calculated. Acceleration data between the positions of the body when the thighs were horizontal and as the knees extended to an angle of 45° indicated that negative acceleration was present at 68.9% of time points, more than predicted by chance.
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