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The traction forces produced between an athlete’s footwear and the playing surface are a crucial factor influencing a player’s performance. Four primary factors affecting traction have been identified from literature: the sports specific movement, the footwear, the playing surface, and the environment. Many authors have investigated traction behaviour mechanically, using a variety of shoe and surface types, concluding that the traction generated at the shoe–surface interface is dependent on each shoe–surface combination (see work by Gheluwe et al., Cawley et al., and Villwocket et al., details given in main text). There has been little attempt in the literature, however, to try and explain the behaviour of the surface from the traction resistance measurements that were observed, perhaps owing to the complex number of variables involved. Furthermore, the variety of methodologies used in past research makes it difficult directly to compare datasets. This paper presents datasets comparing the traction behaviour of several carefully prepared surface systems and states, using three mechanical test procedures, and investigates the factors influencing traction resistance. Results highlight that properties of synthetic turf carpets (fibres and tuft spacing) and the density state of the crumbed rubber infill component and the stud size and configuration influence the maximum traction forces generated at the shoe–surface interface. The magnitude of stud penetration under controlled vertical loading is also presented. The findings of this study further demonstrate the importance of understanding the detail of the surface system under test, and that the infill state has a measurable effect. The design and operation of mechanical traction measurement equipment also demonstrates influences on the traction values measured, and the largest influence is the normal load applied. The FIFA standard test is shown to be less sensitive to infill state than other tests. Recommendations are made for more robust testing methods for future research.

Natural turf pitches are used for many outdoor sports. Turf is a complex network of interacting organic material, soil textures and water content. Turf is susceptible to damage under large surface forces, caused by intensive player movements in rugby union and football. To assess and monitor surface stability, there needs to be a reliable test method for ground staff and other stakeholders. At present, no turf stability mechanical test method exists that represents player-surface interaction, especially to represent a linear movement across the surface such as in a rugby scrummage. This paper describes the development of a novel device for assessing turf stability. Verification was undertaken in the laboratory on a variety of controlled soil samples, and during a field study. The device measurements were shown to be sensitive to the shear strength of a high clay content soil at varying water content and to the density and type of sandy soils. A programme of field data on high quality pitches suggested a large effect of the turf root reinforcement. A conceptual model of soil failure induced by the device was developed to identify the key soil variables and support experimental data interpretation.

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