Cleat-surface friction on new and old AstroTurf.

The authors have studied the alterations in cleat-surface friction of AstroTurf associated with use and exposure. Three cleat types were studied on five year old turf and on an unused, unexposed turf sample of the same production batch. Tests were carried out with and against surface grain under wet and dry conditions. It was found that with use and exposure the surface friction of AstroTurf does change, affecting both player performance and safety.