Background:The aim of this paper studied the strengh of muscle group around shoulder in the female volleyball players with Subacromial Impingement Syndrome(FVPSIS) and the male
weightlifting players with Subacromial Impingement Syndrome(MWPSIS) who were in Guangdong province.
Methods:A sports medicine doctor evaluated the dominant shoulder function of the female volleyball players and the male weightlifting players in Guangdong,then made a definite
diagnosis that Group I were thirteen FVPSIS and Group II were eight female volleyball players with nomal shoulder, and Group III were nine MWPSIS and Group IV were ten male weightlifting players with
nomal shoulder.A examiner measured the dominant shoulder range of motion and the strengh muscle group around shoulder by a electronic tacheometer and a Hoggan MicroFet 2 handheld myodynamia tester
respectively. Results were compared the difference of the shoulder range of motion and the strengh muscle group around shoulder between two group players separately.
Results:Compared with Group II, there were obviously restricted in shoulder flexion and abduction of Group I（p＝0.04）,declined clearly on the strength of upper trapezius （p＝0.001）but
rised on the strength of lower trapezius and serratus anterior muscle（p＝0.04）, changed no apparently on the strength of middle trapezius，fell on the strength of internal rotation and external rotation
of rotator cuff at the frontal plane（p≤0.05），the same to the scapula position（p≤0.05）bur rised evidently on one hundred and twenty degree external rotation（p＝0.001）. Compared with Group IV, there were
obviously restricted in the shoulder flexion,extention and abduction of Group III（p≤0.05）,particularly in the shoulder flexion very clearly（p≤0.01）；declined apparently on the strength of upper
trapezius （p≤0.05），the same to the strength of middle and low trapezius but not clearly, rised on the strength of serratus anterior muscle but not obviously；fell evidently on the strength of internal
rotation and external rotation of rotator cuff at the frontal plane of 60 degree and 90 degree（p≤0.05），especially at the 60 degree internal rotation and the 90 degree external rotation very
apparently（p≤0.01）；drop clearly on the strength of internal rotation and external rotation of rotator cuff at the scapula plane of 60 degree，90 degree and 120 degree（p≤0.05），especially very apparently
external rotation at these three kinds of degree（p≤0.01）.
Conclusions:Compared with players with nomal functional shoulder respectively,It was all decreased the strength of muscle group around shoulder in FVPSS and MWPSS, but the level of
the decline and the compensation due to decline were analyzed targtedly according to different sports.