Competing interests: HTJ reports grants from Amsterdam Movement Science, NOC*NSF, outside the submitted work. RDT reports grants from Dutch National Epilepsy Fund, grants from The Netherlands Organisation for Health Research and Development (ZonMW), grants from NUTS Ohra Fund, grants from Medtronic, grants from Christelijke Vereniging voor de Verpleging van Lijders aan Epilepsie, The Netherlands, grants from AC Thompson Foundation, personal fees from Medtronic, personal fees from UCB, personal fees from GSK, outside the submitted work.