Adaptive effects verified between two plyometric training programs (long SSC versus short SSC) applied to junior volleyball players - Carvalho, A.; Carcalho, C.; Roriz, P.; Cabral, V. (Book of abstracts of the 6th annual congress of the European College of Sport Science, 15th congress of the German Society of Sport Science. Cologne, 24-28 July 2001, 2001)