stroke commonly causes loss of motor function due to weakening of upper / lower extremity 
 muscles1 . according to ryerson2 ,
use the affected upper extremity decreases 
 because of the patient s dependency on the unaffected upper extremity for normal functions , 
 which results in problems such as learned disuse , asymmetric postural patterns , 
 contractures , and aggravated functional restrictions involving the affected upper extremity . 
 therefore , to improve functions of the affected upper extremity in stroke patients , measures 
 that maximize opportunities to use the affectedupper extremity are necessary .
bilateral 
 activities have been discussed as measures to improve the body symmetry and to reduce 
 abnormal muscle tone3 , thereby promoting 
 voluntary movement of the affected upper extremity4 . thus far , bilateral upper extremity coordination movements have 
 been applied in the form of bilateral single exercises utilizing tasks such as figure 
 imitation5 , robot arm upper extremity 
 mechanisms6 and functional 
 stretching7 , and bilateral complex 
 exercises combined with the principle of motor learning , such as rhythmic acoustic8 , unaffected extremity weight addition9 , and active neuromuscular electrical 
 stimulation in stroke patients10 .
most 
 previous studies have reported the positive effects of these exercises on motor function 
 recovery in stroke patients .
whitall et al.8 reported that when chronic hemiplegia patients underwent bilateral 
 training to push and pull upper extremity apparatuses , including acoustic signals , their 
 upper extremity functions were improved . in a study conducted by summer et al.7 with 12 chronic stroke patients ,
the 
 movement time of the patients affected side upper extremity decreased and upper extremity 
 functions showed more improvement when they performed tasks to hold objects by stretching 
 both hands simultaneously then when they performed tasks to hold objects by stretching only 
 one hand .
however , lee su - jin11 advised 
 that the tasks in those studies involved mostly gross motor exercises of the upper extremity 
 and simple repetitive training tasks , and that they were not sufficient to improve patients 
 grasping ability to hold objects with various sizes , shapes , and weights using the shoulder , 
 elbow , wrist , and fingers .
although studies that applied diverse functional training tasks including activities of 
 daily living to symmetric bilateral upper extremity exercises have been conducted 
 recently12 , 13 , these studies are still quite insufficient , and the effects of 
 these new functional tasks on the recovery of upper extremity functions should be compared 
 with those of existing bilateral upper extremity exercises . therefore , the purpose of this study was to compare the effects of symmetric bilateral 
 upper extremity exercises using diverse functional training tasks with the effects of 
 repetitive bilateral upper extremity exercises including acoustic signals on the recovery of 
 upper extremity function and daily living activities in stroke paitents .
forty patients diagnosed with hemiplegia resulting from stroke by a rehabilitation doctor 
 in the n hospital located in daegu , south korea participated in the study . they were 
 randomly and equally assigned to a task - oriented bilateral arm training group ( tbg : 11 
 males , 9 females ) and a repetitive bilateral arm training group ( rbg : 13 males , 7 females ) . 

the meansd age , height , and weight of the patients in the tbg were 51.1514.81  years , 
 163.458.53  cm , and 62.079.79  kg , respectively .
eleven of the 20 patients in the tbg group 
 had right hemiplegia , and 9 had left hemiplegia .
the meansd age , height , and weight of the patients in the rbg were 48.6512.81  years , 
 164.108.11  cm , and 63.809.26  kg , respectively .
eight of the 20 patients had right 
 hemiplegia , and 12 had left hemiplegia .
the inclusion criteria were as follows : no visual field defect , no abnormality in the 
 vestibular organs , no orthopedic disease , an unrestricted range of motion , ability to 
 understand and perform the exercises as instructed by the researcher , a score of 24 or 
 higher on the mini - mental state examination - korean version , and upper extremity paresis with 
 ability to extend the affected wrist and fingers to at least 15 degrees .
this study was 
 approved by the university institutional review board and all the subjects understood the 
 purpose of this study and provided their written informed consent prior to their 
 participation in the study , in accordance with the ethical standards of the declaration of 
 helsinki . the tbg bilateral training with 5 functional tasks such as towel sweep on the table , 
 staking cups , positioning the cup upright , carrying a wooded block , and drinking water .
both groups trained 
 for 5 minutes and had a rest break of 1 minute .
both groups performed their exercises for 30 
 minutes each day , 5 times per week .
measurements were collected twice , before and after the 
 intervention , which lasted for 12 weeks .
the main outcome measurements were box and block 
 test ( bbt ) , jebsen - taylor test ( jbt ) , and modified barthel index ( mbi ) to determine upper 
 limb function and adl ability .
after the general characteristics of the subjects were determined , the 
 paired t - test was used to compare the variations in bbt , jtt , and mbi between pre- and 
 post - intervention within each group .
the significance of the difference between the two 
 groups was investigated using the independent t - test .
both groups demonstrated significant improvement on the bbt , jtt , and mbi after the 
 intervention ( p<0.05 ) ( table 1table 1.comparison of the bbt , jtt , and mbi between pre- and post- intervention of each 
 grouptbgrbgpre - interventionpost - interventionpre - interventionpost - interventionbbt29.40  11.347.7  7.932.8  11.444.1  11.5*jtt45.3  23.361.1  23.155.8  19.564.9  19.9*mbi51.1  17.371.1  19.050.9  20.762.2  21.6*meansd . * significant difference from pre - test at p<0.05 .  
tbg : task oriented bilateral arm 
 training group ; rbg : repetitive bilateral arm training group ; bbt : box and block test ; 
 jtt : jebson - taylor test ; mbi : modified barthel index ) .
the differences in the bbt , jtt , mbi between the 2 groups were compared and 
 were found to be significant ( p<0.05 ) ( table 
 1 ) .
tbg : task oriented bilateral arm 
 training group ; rbg : repetitive bilateral arm training group ; bbt : box and block test ; 
 jtt : jebson - taylor test ; mbi : modified barthel index
this study was conducted to examine the effects of symmetric bilateral upper extremity 
 exercises applied with diverse functional training in comparison with repetitive bilateral 
 upper extremity exercises including acoustic signals on the recovery of upper extremity 
 functions and daily living activities in stroke patients . according to the results of this 
 study , both the tbg and rbg showed significant effects on the recovery of upper extremity 
 motor functions and daily living activities . after implementing the exercise programs , both 
 groups showed significant improvement in the bbt , jtt , and mbi scores . in a study conducted by lin et al.12 on 
 chronic stroke patients who had had the disease for at least 6 months , the group that 
 performed bilateral upper extremity exercises showed further improvement in spatial - temporal 
 control of the affected upper extremity and fugel - meyer assessment scores than the control 
 group . in a study conducted by cauraugh et al.9 ,
2 complex bilateral upper extremity exercise groups were able to 
 move more blocks than the control group in the bbt . in a study conducted by brunner
et 
 al.13 with sub - acute stroke patients 
 that compared the effects of modified constraint induced movement therapy ( mcimt ) with those 
 of bilateral upper extremity training , results indicated that bilateral upper extremity 
 training was as effective as mcimt in the improvement of upper extremity motor functions . 
 according to researchers most sub - acute stroke patients were not required to wear a 
 restraining band during training of the affected upper extremity .
similar to the above - mentioned previous studies , the results of this study indicated that 
 upper extremity functions and daily living activity functions were improved after performing 
 bilateral upper extremity exercises , which supports the opinion that when both hands move 
 simultaneously , instead of acting as separate units , they act as a unit , which is perceived 
 as a coordinated unit by the brain14 .
the 
 study also found that when homologous muscle groups on the left and right sides are 
 activated simultaneously by symmetrical bilateral exercises , the neural networks in the 2 
 cerebral hemispheres that are involved in upper extremity movement on both sides are 
 similarly activated15 . in this study , in comparison with the group that performed repetitive bilateral upper 
 extremity exercises , the group that underwent task - oriented bilateral upper extremity 
 exercise showed significant improvement in the bbt , jtt , and mbi scores .
given this result , 
 functional task training related to movement frequently used in daily life is considered to 
 have more positive effects on the recovery of upper extremity motor functions in stroke 
 patients than repetitive training using simple movement . in a study conducted by wu et al.16 on 
 the performance of stretching motions in chronic stroke patients , kinematically better 
 performance was shown when actual objects used in daily life were used when no such objects 
 were available . in a study conducted by thielman et al.17 , in the case of subjects with low functional levels , coordination 
 between the shoulder and elbow joints was improved when they underwent task - related training 
 than when they performed gradual resistive exercises .
senesac et al.18 conducted a study on 
 whether bilateral arm training with rhythmic auditory cueing ( batrac ) helped the recovery of 
 motor functions the affected upper extremity and whether the effects of the recovery of 
 motor functions would be transmitted to the performance of new tasks .
the subjects underwent 
 batrac for a total of 8 times in 2 weeks , and the effects of the training were evaluated 
 using similar tasks and new tasks . although the maximum speed increased in both tasks , the 
 training did not affect exercise time , speed up areas , or acceleration . with regard to such 
 results
, the researchers presented a stated opinion that if the repetitive bilateral 
 training was composed of significant movement related to the patients daily living 
 activities , the training should have shown positive effects on the recovery of the patients 
 motor functions .
in this study , only the functional aspect of upper extremity exercises was evaluated , and 
 the performance of the exercises was not evaluated kinematically . in future studies , the 
 functional aspect of upper extremity exercises and the kinematic and qualitative aspects of 
 the exercises as well as the recovery in terms of neurophysiology should be evaluated .
based on the results of this study , it can be seen that bilateral upper extremity exercises 
 applied with functional tasks are more effective in improving upper extremity functions and 
 daily living activities in stroke patients compared to simple , repetitive bilateral upper 
 extremity exercises .
therefore , performing symmetrical bilateral upper extremity exercises 
 which utilize treatment tools of different sizes and weights and movements involved in daily 
 living activities , can be used as an effective therapeutic intervention method in the 
 recovery of upper extremity functions and daily living in stroke patients .
 [ purpose ] the purpose of this study was to investigate the effects of task - oriented 
 bilateral arm training and repetitive bilateral arm training on upper limb function and 
 activities of daily living in stroke patients . 
 [ subjects ] forty patients with hemiplegia 
 resulting from stroke were divided into a task orientied bilateral arm training group 
 ( n=20 ) and a repetitive bilateral arm training group ( n=20 ) . 
 [ methods ] the task - oriented 
 group underwent bilateral arm training with 5 functional tasks , and the repetitive group 
 underwent bilateral arm training with rhythmin auditory cueing for 30 minutes / day , 5 
 times / week , for 12 weeks . 
 [ results ] the upper limb function and the ability to perform 
 activities of daily living improved significantly in both groups . 
 although there were 
 significant differences between the groups , the task - oriented group showed greater 
 improvement in upper limb function and activities of daily living . 
 [ conclusion ] we 
 recommend bilateral arm training as well as adding functional task training as a clinical 
 intervention to improve upper limb function activities of daily living in patients with 
 hemiplegia . 