Effects of Arch Support Insole on Vertical GRF Variables and Time to Peak Among ‎Handball Players with Pronated Foot During Jump and Landing Three-Step Shot ‎Technique

The purpose of this study was to determine the effectiveness of Arch Support insole on vertical GRF variables and time to peak compared to healthy group among handball players with pronated foot during jump and landing three-step shot technique.

The current research was semi-experimental pretest-posttest design. The sample consisted of 20 male handball players with pronated foot.  Participants were purposefully assigned into one of two groups: pronated foot and healthy group.The arch support insole used in this study had a bulge on the medial longitudinal arch part. Bartek's force plate device was used to measure the ground reaction force components during the three step jump. Statistical analysis of variance with repeated measurement was used at a significant level of p≤0.05.

The results showed that there was a significant decrease in the anterior-posterior (p=0.004) and vertical (p>0.001) components of the ground reaction force in the pronated foot group during jumping in the post-test phase compared to the pre-test. There was a significant reduce in the time to pick the vertical component of the ground reaction force in the pronated foot group in the post-test compared to the pre-test (p<0.001). Also, There was a significant reduce in the medio-lateral (p=0.001) and vertical (p>0.001) components of the ground reaction force in the pronated foot group in the post-test compared to the pre-test at the moment of landing. In addition, there was a significant increase in the time to pick the vertical component of the ground reaction force in the pronated foot group in the post-test compared to the pre-test (P=0.001).

According to the results of the research, it can be concluded that the use of arch support insoles might lead to reduce ground reaction forces and increase time to pick the components of the ground reaction force during landing and increase ground reaction forces and time to pick during jumping in handball players with pronated foot, that can lead to reduce injuries and better performance.