1. National Research Centre for the Working Environment, 2100 Copenhagen, Denmark
2. Physical Activity and Human Performance group, SMI, Department of Health Science and Technology, Aalborg University, 9220 Aalborg, Denmark
3. National Institute for Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, Netherlands
4. VU University Medical Center, 1081 BT Amsterdam, Netherlands
5. University of Massachusetts Lowell, Lowell, MA 01854, USA
6. Work Research Centre, Dublin, Ireland
7. Department of Psychology, Lund University, Box 213, 221 00 Lund, Sweden
8. Netherlands Organisation for Applied Scientific Research (TNO), Delft, Netherlands