• Physical Therapy Korea
• /
• v.15 no.3
• /
• pp.44-52
• /
• 2008

The purpose of this study was to investigate the effects of different objects and target location of dominant hand on the non-dominant hand movement kinematics in a bimanual reaching task. Fifteen right-handed volunteers were asked to reach from same starting point to the different target point of right and left hand with grasping the objects of different size. Independent variables were 1) three different object types (small mug cup, name pen, and PET bottle), and 2) three different target locations (shorter distance, same distance, and longer distance than the non-dominant hand) of the dominant hand. Dependent variables were movement time (MT), movement distance (MD), movement mean velocity ($MV_{mean}$), and movement peak velocity ($MV_{peak}$) of the non-dominant hand. Repeated measures two-way analysis of variance (ANOVA) was used to test for differences in the non-dominant hand movement kinematics during bimanual reaching. The results of this study were as follows: 1) MT of the non-dominant hand was increased significantly when traveling with grasping the mug cup and reaching the far target location, and was decreased significantly when traveling with grasping the PET bottle and reaching the near target location of the dominant hand. 2) MD of the non-dominant hand was significantly increased during reaching the far target location, and significantly decreased during reaching the near target location with dominant hand. 3) $MV_{mean}$ of the non-dominant hand was increased significantly when traveling with grasping the PET bottle, and was decreased significantly when traveling with grasping the mug cup of the dominant hand. Therefore, it can be concluded that the changes of the ipsilateral hand movement have influence on coupling of the contralateral hand movement in bimanual reaching.

• Physical Therapy Rehabilitation Science
• /
• v.11 no.4
• /
• pp.526-534
• /
• 2022

Objective: The purpose of this study was to compare muscle activities of stroke patients and healthy participants during bimanual tasks. Design: A cross sectional study. Methods: A total of 25 participants (13 hemiparetic stroke patients and 12 healthy participants) were recruited. The muscle activities using electromyogram (EMG) during bimanual tasks were collected from the following muscles: extensor carpi radialis longus (ECRL), biceps brachii (BB), and triceps brachii (TB). The bimanual tasks included eight tasks consisted of (1) raising the wrists up and down, (2) supinating and pronating the palms, (3) touching the shoulder with fingertips, (4) drawing vertical dot, (5) reaching for a cup and bring it in to drink, (6) drawing a circle outward and (7) inward, and (8) grasping the fingers. The EMG data collected from the muscles of paretic and non-paretic sides of stroke patients and the average from both sides of healthy subjects were normalized and compared after calculating the percentage of maximal isometric voluntary contraction. Results: The ECRL, BB and TB of the paretic side of the stroke patients showed relatively greater muscle activity compared to the non-paretic side as well asaverage of the healthy subject duringall tasks (p<0.05). In addition, the ECRL showed the highest muscle activity during most of the tasks. All of the non-paretic side musclesfrom stroke patients showed higher muscle activity compared to those of healthy subjects. Conclusions: The current study showed that muscle activities of upper extremity varied between paretic and non-paretic sides of stroke patients during bimanual tasks. Interestingly, the non-paretic side muscle activities were also different from those of normal participants.