Plyometric’s trainability in preadolescent soccer athletes - Michailidis, Y; Fatouros, I G; Primpa, E; Michailidis, C; Avloniti, A; Chatzinikolaou, A; Barbero-Alvarez, J C; Tsoukas, D; Douroudos, I I; Draganidis, D; Leontsini, D; Margonis, K; Berberidou, F; Kambas, A (J Strength Cond Res, 2013)