Does practising on clay affect the level of motor abilities of tennis players?

Previous research (Elliott et al., 1989, 1990; Muller, 1989; Schönborn, 1984) indicates that the most important factors affecting sports results in tennis performance are coordination, agility, dynamic power and speed, tennis technique, footwork and a group of mental features. It is also well established that agility and footwork as well as speed and power are important components of performance level among tennis players (Elliot et al., 1989, 1990; Królak, 1990; Muller, 1989; Schönborn, 1984, 1993; Unierzyski, 1996). There are also many publications (Higger, 1993, 2002; Pluim, 1999; Snelleman, 1993; Unierzyski et al., 1998; van Aken, 1998) describing training methods for improving these abilities.