6 pages, 10 figures, 27 references. Manuscript presented at ISOPE-2012 conference. Other author's papers can be downloaded at http://www.lama.univ-savoie.fr/~dutykh/International audienceEven though wave run-up is not a new subject, until recently analytical and numerical studies of long wave run-up on a plane beach have failed to identify the existence of resonant regimes. Furthermore, it was a common belief that the leading wave will result in the maximum run-up. Stefanakis et al. (2011) underlined the importance of resonant long wave interactions during run-up and run-down. In the current paper we provide additional results with the use of one-dimensional numerical simulations in the framework of the nonlinear shallow water equations wit...