were conducted using EPSR1. Based on these measurements, 18 of the 19 tested women were diagnosed with significant pes cavus. Results: The experiment revealed a significant reduction in the excessively high metatarsal arch of both feet. The mean load on the metatarsus measured at rest was 0.0% in both feet, and it increased by 0.6% in the left leg ( p ≤ 0.022; Z = 2.293) and by 2.7% in the right leg ( p ≤ 0.023; Z = 2.271). These results suggest that excessive stretching of the plantar fascia and impaired function of the short muscles of the foot lead to a temporary reduction in the arch of the foot. This phenomenon can be compared to stretching a bowstring and its return to the shortest length under static conditions. A statistical analysis of the results of stabilographic measurements revealed significant changes only in the left foot barycenter. An analysis of the ability to maintain postural balance revealed that the observed changes contributed to postural destabilization at p ≤ 0.011 and Z = 2.535. Conclusions: Further research involving electromyography tests is needed to examine plantar muscle tension during isotonic contractions. The duration of the exercise-induced reduction in pes cavus should also be determined for therapeutic purposes.