Putri, Vivi Novia Eka, Yunyun Yudiana, Dikdik Zafar Sidik, Eka Nugraha, and Tutur Jatmiko. 2024. “The OPT (Optimum Performance Training) Method for 12 Weeks Increases Strength and Power of Female Athletes from the Indonesian National Beach Volleyball Team”. Jurnal SPORTIF : Jurnal Penelitian Pembelajaran 10 (3):405-19. https://doi.org/10.29407/js_unpgri.v10i3.23200.