The data was collected for the ABS: Always Stay Active! study funded by ZonMW Sportinnovator (grant no.: 538001037). The original aim of this study was to test the extent to which two different motivational stimuli affected runners who enrolled for the 7Hills running event for the first time with respect to: (1) training frequency and training volume; (2) the likelihood to start at the 7Hills running event; (3) self-declared motivations for running activities; (4) the likelihood to register for subsequent running events. Respondents filled in a web-survey three times: (t1 pre-treatment; t2 treatment; t3 post-treatment). Due to the outbreak of the Covid-19 pandemic in 2020, we broadened the goal of this study and included in the third wave additional questions to assess how Covid-19 and the restriction measures taken affected running behaviour and motivation.