Sport is not only a social phenomenon of our world but a privileged field of human and social behavior research. There has been tremendous growth and specialization of sport science over recent decades and this fragmentation process has been challenged with the motif of the 18th Congress of the European College of Sport Science: Unifying Sport Science. The motif seeks to move from specialization to integration, from engineering to a biologically-based conception of living systems, from multi-to trandisciplinary research. A question arises: is it possible to integrate the fragmented areas and facilitate the transfer of theoretical explanatory principles, techniques and insights between disciplines? On the basis of the contributions to the congress, this paper aims to introduce scientific approaches, already widespread in physics, chemistry, biology (including omics) and the social sciences, which focused on the dynamic complex interactions between system components (proteins, cells, organisms, groups, societies), reveal general explanatory principles and contribute to the unification of knowledge. The purpose is to encourage sport scientists to devise new ways of research and try to complement, not replace, the dominant approaches in sport science with the hope that going from the parts to the whole and from the whole to the parts will help scientists to recognize the right paths.<\/p>\n\n