Football-specific evaluation of player–surface interaction on different football turf systems

In order to accommodate the increasing relevance of artificial football turf systems, both producers as well as governing bodies make substantial efforts to bring the game on artificial turf as close as possible to the game played on natural grass. In this context, the certifications for acceptance of certain artificial turf systems are based on pure mechanical tests. Developers modify mainly fibres, infill and elastic layer in order to optimize the mechanical properties of the turf system. Some recent research shows that pure mechanical tests of artificial turf systems do not reflect the interaction between the player and the surface. In complex football-specific movements such as goal kicks or cuttings the players’ perception, movement and sports performance can change remarkably due to changes in the turf. Those changes are not necessarily reflected in mechanical tests. By basically changing one component (infill), the differences between artificial turfs can become greater than those between natural grass and an artificial system. It is likely that physiological processes are also influenced. Subject tests are recommended to improve the current certification procedures and to provide information to the producers in order to optimize existing systems. More research is required in order to produce baseline data for soccer-specific movements on natural grass.