Gómez-Bruton, Alejandro Navarrete-Villanueva, David Pérez-Gómez, Jorge Vila-Maldonado, Sara Gesteiro, Eva Gusi, Narcis Villa-Vicente, José G. Espino, Luis González-Gross, Marcela Casajús, José A. Ara, Ignacio Gómez-Cabello, Alba Vicente-Rodríguez, Germán The effects of age, organized physical activity and sedentarism on fitness in older adults: An 8-year longitudinal study Int. j. environ. res. public health 10.3390/ijerph17124312 2020 2020