Author Contributions
B.S. initiated and directed FitMum. S.A.A., S.d.P.K., C.B.R., J.M.B., T.D.C., S.M., E.L. and B.S. developed the study protocol. S.d.P.K. and C.B.R. conducted intervention activities and collected data assisted by S.A.A., research assistants, and master students. E.L. was the clinical trial manager and supervised the clinical part of FitMum in collaboration with J.M.B., T.D.C., S.M. and B.S., S.A.A. performed the activity tracker data management and performed statistical analyses. A.K.J. supervised the statistical analyses. J.E.L. contributed with expertise in self-tracking, and P.J. contributed with expertise in sleep medicine. S.A.A. drafted the manuscript, supervised by B.S. All authors have read and agreed to the published version of the manuscript.