Objectives Characterise usability, safety, comfort, and impact on productivity of treadmill workstations in real worksites.

Method Office workers volunteered to try out for six months a treadmill workstation consisting of a height adjustable electric desk, a walking treadmill, and their own sitting device (chair or “sitting ball”). They were instructed to set up and use the workstation at will. Monthly individual and group meetings were performed to gather qualitative data.

Results USABILITY: Difficult set up of the workstation, which demanded use of wireless mouse and keyboards and generated creative arrangements. Unanimous love for the adjustable electric desk. Difficult to talk to people while walking (disrespectful, “On the treadmill we are taller” - affect hierarchies). SAFETY: There was no event of either trips or falls. COMFORT: An important difficulty was during the first weeks to get used to longer time in standing position. In average it took two weeks for discomfort symptoms in foot and knees to recede. PRODUCTIVITY: faster speed implies faster impact on productivity. 7–.8 mph was the most used and comfortable speed. Walking on the treadmill was not compatible with drawing or working with spreadsheets.

Conclusions Treadmill workstation did not meet workers’ expectations but the electric adjustable desk exceeded those expectations. Guiding and external motivation to increase use would be accepted and expected. DESIGN RECOMMENDATIONS: Reduce maximum speed. Even 2.0 mph is too much. Additional design study needed to improve global workstation setup without decreasing flexibility and adaptation of the station.