Sitting volleyball classification system : the athletes' perspective - Marszałek, Jolanta (Jozef Pilsudski University of Physical Education in Warsaw (Polònia). Faculty of Rehabilitation) ; Molik, Bartosz (Jozef Pilsudski University of Physical Education in Warsaw (Polònia). Faculty of Rehabilitation) ; Gómez Ruano, Miguel Ángel (Universidad Politécnica de Madrid. Facultad de Ciencias de la Actividad Física y del Deporte) ; Skučas, Kęstutis (Lithuanian Sports University in Kaunas) ; Pokvytyte, Vaida (Lithuanian Sports University in Kaunas) ; Lencse Mucha, Judit (Jozef Pilsudski University of Physical Education in Warsaw (Polònia). Faculty of Rehabilitation) ; Rekowski, Witold (Jozef Pilsudski University of Physical Education in Warsaw (Polònia). Faculty of Rehabilitation)