a stroke is a central nervous system disease that has a serious impact on individuals 
 lives1 . depending on the lesion area , 
 strokes cause diverse and complex functional disabilities , including decreased motor 
 function , sensory loss , and impaired balance ability2 , 
 3 . stroke patients also experience 
 restricted performance of the functional motions necessary for ordinary life , and reduced 
 gait ability4 , 5 . to support the many body postures needed in everyday life , maintenance of appropriate trunk 
 muscle strength and endurance are very important6 . the abdominal and trunk muscles maintain the stability of the lower 
 trunk , and they are important for trunk movement and motor control7 . dickstein et al.8 demonstrated the significance of trunk muscles by verifying a 
 decrease in anticipatory postural adjustments in hemiplegic patients compared to healthy 
 subjects , based on a comparison of left and right trunk muscle onset time through movement 
 of the upper and lower extremities . therefore , to improve the abilities of chronic stroke 
 patients , it is important to ensure functioning postural stability during movement training . this requires activation of the trunk muscles . a representative technique for achieving this 
 is the bracing method . bracing involves stabilizing the trunk by increasing internal 
 abdominal pressure through the action activation of 29 pairs of deep and superficial 
 muscles9 . accordingly , this study 
 examined the effects of upper extremity task training with the bracing method applied on 
 trunk adjustment ability and balance in stroke patients . as subjects , this study selected 46 non - traumatic hemiplegic stroke patients in at r , h , 
 and b hospitals whose onset of stroke had occurred at least six months earlier . all 
 demonstrated an understanding of the experimental process before they agreed to participate 
 in the experiment . ( all scored at least 24 on the korean version of the mini - mental state 
 examination . ) they were able to sit unassisted for five minutes or longer without special 
 equipment . the subjects were able to understand and follow the therapist s directions and 
 had no other neurological problems ( vision , hearing , other senses ) or orthopedic damage 
 ( table 1table 1.general characteristics of the subjectsexperimental group ( n=23)control group ( n=23)age ( yrs)60.4  10.558.1  10.7height ( cm)164.0  8.6164.4  8.2weight ( kg)65.8  10.563.5  9.8gendermale13 ( 56.5)14 ( 60.9)female10 ( 43.5)9 ( 39.1)affected sideleft7 ( 30.0)10 ( 43.5)right16 ( 69.6)13 ( 56.5)time since stroke ( months)17.7  10.416.5  11.2mean  standard deviation ; n ( % ) ) . all protocols were approved by the university of daejeon . before 
 participation , the procedures , risks , and benefits mean  standard deviation ; n ( % ) the subjects of the experimental group ( upper extremity task - training group with symmetric 
 abdominal muscle contraction ) received upper extremity task training while maintaining 
 symmetric abdominal muscle contraction ( referred to here as  bracing  ) . sounds while they concurrently contracted left and right and forward and backward trunk 
 muscles isometrically for five seconds as if force was given to the abdomen reflexively , and 
 while maintaining hallow respiration . the control group ( general upper extremity task - training group ) received upper extremity 
 task training . during the training , each subject sat on a chair with the back . they flexed 
 the hip , knee , and ankle joints of both lower extremities by 90 degrees and placed both feet 
 on the floor . they were instructed to utilize only the paretic upper extremity and were 
 assisted in the movement so that they did not exert compensatory strategies . six numbered 
 tasks were performed in sequence for five to six minutes . the order and duration of the 
 tasks for example , subjects who showed 
 good function in one task were asked to stop and move on to the next task . if they were not 
 able to perform the next task due to poor function , they performed the previous task for an 
 extended amount of time . the postural assessment scale for stroke ( pass ) and trunk impairment scale ( tis ) were 
 utilized to evaluate subjects postures and assess balance . the balance performance monitor 
 ( bpm ) was employed and biorescue software ( ap 1153 rm ingenierie , rodez , france ) was 
 utilized to evaluate static balance ability and limit of stability ( los ) . pasw statistics 18.0 for windows ( ibm / spss inc , chicago , il , usa ) was used for all 
 statistical analyses performed in this study . the general characteristics of each group were 
 analyzed using a  test and an independent t - test . to compare differences in 
 pre- and post - training results between the two groups over time , an independent samples 
 t - test was utilized . to determine the statistical significance of data over time within each 
 group , a paired t - test was employed . table 2table 2.a comparison of postural assessment scale for stroke , trunk impairment scale 
 scoresexperimental group ( n=23)control group ( n=23)pass ( score)pre - test21.7  7.421.0  7.0post - test22.4  7.021.5  6.7tis ( score)pre - test13.0  4.312.5  4.6post - test14.4  4.313.1  4.4mean  standard deviation . * significant difference within group ( pre - test vs. post - test ) . significant difference between groups ( experimental group vs. control 
 group ) shows the results of posture comparisons between the experimental group and 
 the control group before and after intervention . the experimental group s tis scores 
 significantly increased after the intervention ( p<0.05 ) , whereas the control group did 
 not see any significant difference . table 
 3table 3.a comparison of center of pressure and limit of stabilityexperimental group ( n=23)control group ( n=23)cop ( cm)pre - test5.39  2.825.65  3.13post - test3.98 2.314.80  2.93*los ( mm)pre - test8,443.4  1,545.78,440.4  1,573.3post - test8,866.0  1,611.08,651.0  1,610.7*mean  standard deviation . * significant difference between groups ( experimental group vs. control 
 group ) displays the results of a comparison of pre- and post - intervention balance 
 evaluations between the groups . there was significant improvement in balance after the 
 intervention in both the experimental group and the control group . according to the 
 between - group comparisons , the improvements in the experimental group were significantly 
 greater in the control group ( p<0.05 ) , except in the postural assessment scale ( pass ) 
 ( p>0.05 ) . significant difference between groups ( experimental group vs. control 
 group ) mean  standard deviation . this study applied upper extremity task training with symmetric abdominal muscle 
 contraction as a method of improving postural adjustment in adult hemiplegic patients and 
 examined its effect on postural adjustment . the pre- and post - exercise values of tis scores 
 were significantly different in both groups , and a significant difference was seen between 
 the two groups . a study by allison et al.10 featuring bracing - assisted trunk stabilization exercises showed 
 heightened activity of the trunk muscles and improved trunk function , which is consistent 
 with the results of the present study . the stroke postural evaluation scores of both groups 
 increased , but no significant difference was seen between them . this is consistent with a 
 study of sub - acute state patients by benaim et al.11 , which showed that a short intervention period of six weeks 
 resulted in no significant difference . in the static balance test , significant differences 
 were seen within both groups in pre- and post - exercise results , as well as in the scores 
 between the two groups . this is consistent with the results of research by brown et al.12 , which show that short muscle contraction 
 initiation times enabled anticipatory postural adjustments , and that postural adjustment 
 affected balance . in the los test , both groups saw significant differences in pre- and 
 post - exercise results ; a significant difference was also seen between the results of the two 
 groups after the exercise . hodge and richardson13 report that intervention in the deep abdominal muscles through 
 trunk stabilization exercises was more effective than other forms of exercise in achieving 
 improved movement of the four limbs and postural adjustment ability ; this is consistent with 
 the present study s results . the limitations of this study were the short intervention 
 period of six weeks and the small number of experimental participants satisfying selection 
 criteria . based on the results of this study , upper limb task training with symmetric 
 abdominal muscle contraction , applied as part of trunk stabilization exercises in adult 
 hemiplegic patients , may be applied to diverse hemiplegic patients in the clinical field and 
 be implemented as an exercise program for them after discharge from hospital .
[ purpose ] the purpose of this study is to examine the effects of upper extremity task 
 training employing the bracing method on the trunk control and balance of stroke patients . 
 [ subjects and methods ] the subjects were 46 stroke patients whose strokes had occurred six 
 months or more prior to the study . 
 the subjects were divided into two groups . 
 one group 
 underwent upper extremity task training with symmetric abdominal muscle contraction 
 ( bracing ) applied . 
 the other group simply underwent upper extremity task training , without 
 bracing . 
 [ results ] the experimental group s trunk impairment scale ( tis ) significantly 
 increased after the intervention , whereas the control group did not see any significant 
 difference . 
 there was significant improvement in balance after the intervention in both 
 the experimental group and the control group . 
 according to the between - group comparisons , 
 the improvements in the experimental group were significantly greater in the control 
 group , except in the postural assessment scale ( pass ) . 
 [ conclusion ] based on the results 
 of this study , upper extremity task exercises with symmetric abdominal muscle contraction , 
 conducted as part of adult hemiplegic patients trunk stabilization exercises , can be 
 applied to a diverse range of hemiplegic patients and implemented as an exercise program 
 after discharge from hospital .