Marques, António T.Maia, José A.R.Silva, Rui GargantaSeabra, AndréPrista, AntónioBustamante, AlcibíadesVinagre, JoãoLopes, Vitor P.2011-05-042011-05-042006Marques, A.T.; Maia, José, A.R.; Garganta, R.; Seabra, A.; Prista, A.; Bustamante, A.; Vinagre, J.; Lopes, Vítor P. (2006). How many days to monitor levels of physical activity in children? A generalizability approach. In Medicine and Science in Sports and Exercise. Denver0195-9131http://hdl.handle.net/10198/4153There has been some debate about the number of days to monitor physical activity (PA). This discussion is relevant to have reliable estimates (means and variances) of PA of children and adolescents. Still, the approach taken so far, has not dealt with different levels of daily physical activity in children.engconference object