PURPOSE To show biomechanically that the brachioradialis (BR) muscle can be transferred to restore key pinch and forearm pronation simultaneously. METHODS Nine fresh-frozen forearms were thawed and instrumented with a custom muscle-tendon excursion jig. Maximum BR muscle-tendon excursion was measured with the wrist and thumb mobile. Muscle-tendon excursion then was measured from 60 degrees of...

In this paper, we introduce a new mode of mechanomyography (MMG) signal capture for enhancing the performance human-machine interfaces (HMIs) through modulation normal pressure at sensor location. Utilizing novel approach, increased MMG resolution is enabled by tunable degree freedom to sensor-skin contact area. We detail mechatronic design, experimental validation, and user study an armband wi...

This study investigated transmission of corticospinal output through motoneurons over a wide range of voluntary contraction strengths in humans. During voluntary contraction of biceps brachii, motor evoked potentials (MEPs) to transcranial magnetic stimulation of the motor cortex grow up to about 50% maximal force and then decrease. To determine whether the decrease reflects events at a cortica...

The purpose of this study was to explore the effects of fall type and fall height on the kinematics, kinetics, and muscle activation of the upper extremity during simulated forward falls using a novel fall simulation method. Twenty participants were released in a prone position from a Propelled Upper Limb Fall ARrest Impact System. Impacts occurred to the hands from two fall heights (0.05m and ...

Impaired torque production is a major physical impairment following stroke, and has been studied extensively in isometric conditions. However, functional use of a limb requires torque production during movement, and the effects of velocity on maximal torque production may be abnormally enhanced in the paretic limb. The purpose of this study was to quantify the effects of movement velocity on ma...

The corticospinal system plays an important role in control of voluntary movements in primates. Recently, we demonstrated that the effectiveness of this system is depressed after maximal exercise. Because the depression was absent after antidromic activation of the motoneurons, we argued that transmission across corticospinal synapses was involved. Here, we explore the possible functional conse...

the purpose of this study was to estimate the torque from high‑density surface electromyography signals of biceps brachii, brachioradialis, and the medial and lateral heads of triceps brachii muscles during moderate‑to‑high isometric elbow flexion‑extension. the elbow torque was estimated in two following steps: first, surface electromyography (emg) amplitudes were estimated using principal com...

1 Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland 2 Institute of Sport and Sport Science, University of Freiburg, Germany 3 Department of Trainingand Movement Science, University of Potsdam, Germany 4 Laboratory of Biomechanics, University of Ljubljana, Slovenia 5 Department of Mechanical Engineering, University of Lappeenranta, Finland

In martial arts and contact sports strikes are performed at near maximum speeds. For that reason, electromyography (EMG) analysis of such movements is non-trivial. This paper has three main goals: firstly, to investigate the differences in the EMG activity of muscles during strikes performed with and without impacts; secondly, to assess the advantages of using Sum of Significant Power (SSP) val...