1. 1 Kristiania University College, School of Health Sciences, Departement of Health and Exercise , Prinsens gate 7-9 , Oslo , Norway
2. 2 Kristiania University College, School of Health Sciences, Departement of Health and Exercise , Prinsens gate 7-9 , Oslo , Norway
3. 3 Kristiania University College, School of Health Sciences, Departement of Health and Exercise , Prinsens gate 7-9 , Oslo , Norway
4. 4 Kristiania University College, School of Health Sciences, Departement of Psychology , Pedagogy and Law, Kalfarveien 78C , Bergen , Norway