1. Aix Marseille Univ, CNRS, Inst Sci Mouvement, Marseille, France
2. albertha.van-opstal@univ-amu.fr
3. remy.casanova@univ-amu.fr
4. University Medical Center Groningen, Department of Human Movement Sciences, Groningen, The Netherlands
5. f.t.j.m.zaal@umcg.nl
6. reinoud.bootsma@univ-amu.fr