abnormal scapular alignment and kinematics during arm elevation , disturbs normal shoulder 
 kinematics1 , 2 . therefore in rehabilitation , retraining the scapulothoracic 
 musculature is necessary for regaining normal alignment of the shoulder girdle and for 
 functional shoulder movement1,2,3 . closed kinetic 
 chain exercises for the upper extremity are known to activate both the scapulothoracic and 
 shoulder musculatures3 , 4 . a recent finding suggested that the wall push up plus exercise is 
 an appropriate closed kinetic exercise for those requiring low - level strengthening 
 exercise5 . however , the general wall 
 push up plus exercise is unable to stimulate proprioception of the shoulder joint receptors 
 due to reduced tension , and simply introducing scapular protraction movement is 
 questionable , since it is a less functional exercise than excises including an arm elevation 
 component6 . in clinical practice , there 
 are few devices for activating the musculature of the upper extremity . although the shoulder 
 press , pull down , and cross cable device are common exercise machine , these devices are not 
 portable , and are not easy for individual to adjust patients . therefore , the present study 
 investigated the effect of a newly developed device which provides tensile resistance and 
 induces an arm elevation component to scapulothoracic exercise . fifteen male subjects who were right - arm dominant participated in this study . they were 
 aged 20 to 26  years ( 21.92.8 ) , and their mean height and weight were 174.90.0  cm , and 
 66.55.3  kg , respectively . subjects were excluded if they had a history of upper extremity 
 injury within the last 6 months . this study was approved by the inje university faculty of 
 health sciences human ethics committee . electromyographic ( emg ) recordings of the upper 
 trapezius ( ut ) , lower trapezius ( lt ) , middle serratus anterior ( msa ) , lower serratus 
 anterior ( lsa ) , and pectoralis major ( pm ) were performed using a trigno wireless system 
 ( delsys , boston , ma , usa ) . electrode placements and the procedure for measuring maximal 
 voluntary contraction ( mvc ) were followed recommendations in the literature7 , 8 . we 
 designed a wall slide device ( wsd ) , which is an adaptation of the standard push up bar . handle bars are 
 connected to the trunk belt by a detachable theraband ( fig . wall slide device ( a : initial posture , b : terminal posture ) ) . each subject performed three trials of general wall push - up plus ( wpup ) and wall 
 slide with device ( wsd ) exercises . in the wpup , subjects stood at arms length from the wall , 
 and pushed against the wall to push their back backward maximally . in the wsd exercise , 
 subjects grasped the wsd bar and elevated the arm from 90 to 120. the two exercises were 
 performed in a random order . significance was 
 accepted for values of p<0.05 , and spss version 18.0 was used for statistical 
 analyses . during the wsd exercise , the averaged % mvc data of ut , msa , and lsa were 25.217.5 , 
 63.531.4 , and 56.416.7 , respectively . the % mvc data of the wsd were significantly higher 
 than those of the wpup ( p<0.05 ) , which were 10.413 for ut , 43.116 for msa , and 3816.3 
 for lsa . there were no significant differences in % mvc data of lt and pm between the wpup 
 ( 11.612.5 for lt , 12.312.9 for pm ) and the wsd ( 16.118.79 for lt , 95.61 for pm ) 
 exercises ( p>0.05 ) . a previous study categorized the level of % mvc into 4 levels : low , 020% ; moderate , 2140% ; 
 high , 4160% ; very high , > 60%9 . 
 following this criteria , the wpup of our present induced moderate levels of muscle 
 activation in msa and lsa . while wsd induced a moderate level of ut activation as well as 
 high levels of msa and lsa activation . this suggests that the newly designed wsd exercise 
 activates the scapulothoracic musculature more efficiently and more harmoniously than the 
 wpup . although some previous reports have cautioned against excessive activation of the 
 ut5 , 7 , it contributes to upward rotation of the scapulae , and one previous 
 study demonstrated that loss of ut function causes reduced scapular upward rotation10 . in the case of a patient with shoulder 
 disability , although previous studies have suggested using unstable surfaces and changes of body 
 position to increase muscular activation7 , 11 , providing controlled resistance and 
 inducing functional movement can not be easily adjusted to suit the patients . the newly 
 designed wsd includes wheels to reduce friction resistance during the wall slide exercise , 
 and resistance to raising the arms can be easily controlled by changing the length or type 
 of theraband . futher comparisons of the wsd exercise with other exercise devices and 
 exercise methods are required . our present results suggest that exercise using the wsd can 
 more effectively activate the scapulothoraic musculature than the general wpup .
[ purpose ] the purpose of this study was to evaluate the effect of the wall slide device 
 on activation of the scapulothoracic musculature . [ subjects ] we recruited 15 healthy male 
 subjects . 
 [ methods ] the subjects performed the general wall push - up plus ( wpup ) and the 
 wall slide with device ( wsd ) exercises . during the exercises , the muscle activities of the 
 upper and lower trapezius ( ut , lt ) , middle and lower serratus anterior ( msa , lsa ) , and 
 pectoralis major ( pm ) were measured . 
 [ results ] the normalized muscle activity data of the 
 wsd were significantly higher in ut , msa and lsa than the wpup . [ conclusion ] our results 
 suggest that exercise using the wsd can more effectively activate the scapulothoracic 
 musculature than the general wpup .