Effect of elbow flection on grip strength in vertical and horizontal directions.

In this study the effect of elbow flexion with forward flexion of the upper arm and shoulder rotation on the maximum voluntary contraction (MVC) of grip strength was investigated. Two directions (vertical and horizontal), three positions (left side, central and right) and five elbow flexion angles were taken as independent variables. The analysis of variances (ANOVA) was performed on the data collected. The results of the analysis showed that there was highly significant effect of the direction, front position of the wrist (the line in front of the right shoulder, centre of the chest and left shoulder using the right hand in the sagittal plane), and the elbow flexion angle on MVC grip strength. The left position has significantly low grip strength compared to the right position for right-hand participants. The two-way interactions of all the three main factors were found significant. The three-way interaction was not found significant. Further one-way ANOVAs showed that the effect of the direction (vertical/horizontal) was not found significant on any of the levels of the position and elbow flexion in the simple main effects analysis (p > 0.05).