Background: This study investigates the effects of tibialis posterior (TP) and peroneus longus muscle (PL) exercises with short foot (SF) exercises on dynamic balance control, plantar pressure, and TP and PL strength in individuals with flexible flatfoot.

Methods: This experimental study was conducted at Kasetsart University in Thailand. Twenty individuals (12 males and 8 females, aged 18–22 years) with flexible flatfoot were divided into a control group (n = 10) and an experimental group (n = 10). A control group performed the SF exercise only. The experimental group performed the TP, PL, and SF exercises. The exercise duration was 6 weeks. Both groups performed the exercises three times each week. Dynamic balance control, plantar pressure while walking, and TP and PL muscle strength were assessed before and after the 6-week exercise program.

Results: At the end of the 6-week period, dynamic balance control, as well as TP and PL strength, were significantly different between the two groups (p < 0.05); the experimental group had a better balance control and greater strength than the control group. No statistically significant between-group difference in plantar pressure was found. However, slight reductions in plantar pressure after the 6-week program were observed in the experimental group.

Conclusions: TP and PL exercises with SF exercises helped improve dynamic balance control and TP and PL strength, which support the medial longitudinal arch (MLA), in individuals with flexible flatfoot. In addition, exercises tended to reduce plantar pressure in individuals with flexible flatfoot.


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