The Effects Running Surfaces have on Injury
             The purpose of this paper is to provide a description of the influence that sport surfaces have on injury. It may help to understand how specific sports surfaces effect athletes, while listing the advantages and disadvantages of such sports surfaces to the runner. Running surfaces cause many sports and exercise injuries because of the frequency of contact between the shoe and the surface. Changes in surface characteristics can alter not only the ground reaction force but also the activation patterns of the major leg muscles. This type of sports surface has both positive and negative effects on the performer. A change of surface may necessitate a modification of technique. The change of force acting on the performer alters the type of injury. This paper will examine the different characteristics, the biomechanics, as well as the injury aspects of sports surfaces.
             Sport surfaces are often complex structures with several layers, all of which contribute to the overall behavior of the surface. Friction and traction are characteristics that are directly related to the behavior of surfaces for sport and exercise and have the greatest association with injury (Bartlett, 1997).
             The friction or traction force between a shoe or other object and a surface is the force component peripheral to the surface (Bloom, 1997). In friction of smooth materials, the force is generated by 'force locking', and the maximum friction force depends on the coefficient of sliding friction (u) between the two materials in contact. Traction is the
             term used when the force is generated by interlocking of the contacting objects, such as spikes penetrating a Tartan track, known as 'form locking' (Bartlett, 1997). This friction or traction force is particularly important in running, which the coefficient of friction or traction should exceed 1.0 and for changes of direction such as swerves and tur...