The Most Effective Exercise for Strengthening the Supraspinatus : Evaluation by Magnetic Resonance Imaging by TAKEDA Yoshitsugu and ENDO Kenji Department of Orthopedic Surgery, The University of Tokushima School of Medicine Abstract To determine the most effective exercise for the supraspinatus, we measured T2 relaxation time (T2) for the rotator cuff and deltoid before and after three type of exercise ("empty can", "full can", "horizontal abduction in the prone position" ) on MRI. Six males performed three sets of each exercise with a weight of 20 repetitive maximum. Subjects were imaged before and immediately after the exercise. T2 for rotator cuff and deltoid on sagittal MR images were calculated using the software routines on the MRI system. An increase in T2 for the supraspinatus after the empty can and full can exercises (10.5±2.0, 10.5±2.0 respectively) was significantly higher than that after the horizontal abduction (.63 ±1.3). There was no significant difference in the value for the supraspinatus between the empty can and full can exercises. This study has demonstrated that the horizontal abduction exercise is less effective for strengthening the supraspinatus than the empty can and full can exercises. We found no significant differences in loading of the supraspinatus between the empty can and full can exercises Therefore, the full can exercise should be used for rehabilitation provocation due to subacromial impingement., because it involves less risk of pain. Key words ; (Supraspinatus),MRI (Magnetic Resonance Imaging) (Muscle strength)
The Shoulder Joint, 2001 ; Vol. 25, Na2 : 267-271. Empty can exercise ost hoc test (Tukey-Kramer) dual fine wire EMG Empty can exercise empty can exercise
Increase Increase In Horizontal abduction exercise Horizontal abduction exercise Full Can Empty Can Horizontal Abduction Increase In Muscle One - factor ANOVA: * p < 0.05 Horizontal abduction Empty can Full can exercise Calculated a; Empty can exercise b; Empty can exercise c; Full can exercise d; Full can exercise e; Horizontal abduction exercise f; Horizontal abduction exercise Image.
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