Comparing the Immediate and Long-Term Effects of Arch Support on the Electrical Activity of Muscles During Landing in Three Steps Shot Technique in Handball Players with Pronation Foot.

Pronation of foot is one of the most common abnormalities of the lower limb; so the purpose of this study was to compare the immediate and long-term effects of arch support on the electrical activity of muscles during landing in the three-step shot technique in handball players with pronation foot.

The present study was semi-experimental with a pre-test and post-test design with a control group. The statistical population of this research was male handball players with pronated foot. Sampling was done using convenient sampling method, and 10 people with pronated foot along with 10 healthy people were selected. The sole of the shoe used in this study had a protrusion on the inner edge of the foot (Arch support). To measure the electrical activity of the muscles of the lower limbs, it was recorded by an electromyography device and analyzed by the biometric datalite program. ANOVA test with repeated measurements was used to analyze the data, and the independent t-test was used to check the sameness of the initial conditions.

The results showed that there were significant increases in gastrocnemius muscles (P=0.04), vastus medialis (p=0.001), and biceps femoris muscles (p=0.089) in the pronation foot group after 4 weeks of using arch support insoles compared to the pre-test stage. Also, there was a significant increase in the vastus medialis muscle (p=0.06) in the pronation group in the immediate stage compared to the pre-test stage. In addition, the semitendinosus muscle in the pronation group had a significant increase after 4 weeks compared to the immediate phase (p=0.035).

It seems that in addition to improving the electrical activity of the lower limb muscles during jumping and landing, the immediate and long-term use of Arch Support insoles can lead to improved balance, absorption of landing shocks, and stability of the ankle joint in handball players with pronation foot.