Vibration and Rebound Velocity Characteristics of Conventional and Oversized Tennis Rackets

Abstract

Stroboscope photography and accelerometry techniques were used to measure rebound velocities of tennis balls from impact locations on the strings and vibration levels at the rotation point on the racket handle for both conventional and oversized tennis rackets. The oversized rackets demonstrated lower vibration levels and higher rebound velocities than their conventional counterparts when balls struck by the racket were compared along a transverse axis drawn perpendicular to the racket shaft and through the geometric center of the strings. These differences were, however, only significantly different (p < .01) at the impact location 6 cm along this axis toward the top edge of the racket. Higher rebound velocities were recorded at all impact points from the oversized rackets along the axis in line with the racket shaft. Significantly lower vibration levels were apparent at locations 4 cm, 6 cm, and 8 cm from the string center away from the racket handle. The lower vibration levels, particularly at the extremes of the racket face, in conjunction with higher rebound velocities, support the concept that this new racket design is of practical benefit to users.