A comparison of two shoulder exercises utilizing isotonic, isokinetic, and electromyographic analyses.

Abstract

This purpose of this study was to compare the seated side-lateral raise to the seated behind-the-neck press exercises, utilizing isotonic, isokinetic, and electromyographic analyses. Sixty-four male students participated in this study. Experimental group A (N = 22) used the seated side-lateral raise exercise. Experimental group B (N = 23) used the seated behind-the-neck press exercise. Control group C (N = 19) used no treatment.

Subjects for the experimental groups performed 10 pretest and posttest repetitions at maximum weight with their particular exercise. The difference determined isotonic gains. Experimental groups A and B and control group C were tested for shoulder abduction isokinetic strength on the Cybex 340 at 60 degrees per second and 180 degrees per second.

The pretest was followed by a 10-week treatment period for experimental groups A and B. The treatment for both experimentals group A and B consisted of three sets of 10 repetitions of the seated side-lateral raise. The treatment for experimental group B consisted of three sets of 10 repetitions. Control group C had no treatment for the 10-week period. Five volunteers participated in the electromyography study. The muscles analyzed were the anterior, middle and posterior deltoids; the triceps; and the supraspinatus. Each subject performed three repetitions for the seated side-lateral raise and the seated behind-the-neck press.

Results showed that after a 10-week treatment period, both experimental groups A and B showed significantly greater weight gains isotonically. Isokinetically, there was no significant difference at 60 degrees per second among groups A, B, and C. At 180 degrees per second, there was no difference between groups A and B. There was significance between groups A and C and significance between groups B and C.

The results of the electromyographic analyses showed that during the seated side-lateral raise, the posterior deltoid and the triceps were the least involved. The supraspinatus was the most involved, followed by the anterior and middle deltoids. During the seated behind-the-neck press, the posterior deltoid was the least involved, followed by the anterior and middle deltoids. The muscles most involved were the triceps and supraspinatus for this exercise.