Button damper reduces the impact force during tennis flat serve.

Abstract

Problem Statement: The effect of damper on the impact force and damping time is still controversial and no literature review has compared dampers with varied string tension.Approach: Experimental study Purpose: To study the effect of four dampers on tennis rackets on the impact force and damping time at the grip area at low and high tennis racket string tension. MaterialsandMethods: The peak force and damping time were tested on tennis racket grips with five settings: no damper and four different dampers. Tennis balls were served using a tennis strike-simulating machine at a racket speed of 32 m/s. The impact force and damping time were recorded using a force transducer attached to the grip and were compared at the low and high string tensions. Results: Button damperreduced the impact force at the grip regardless of the string tension. At low string tension, the force was 144.6 ± 0 N with no damper compared to 133.5 ± 7.8 N when button damperwas installed (p = 0.006); similarly, at high string tension, the forces were 171.2 ± 6.1 N and 157.9 ± 4.9 N, respectively (p = 0.00). Moreover, at low string tension, button damperyielded a 10% decrease in damping time (from 380.2 ± 10.3 ms to 344.0 ± 25.8 ms; p= 0.013). Similarly, rubber band damperexhibited a 15% decrease in damping time at low string tension (from 380.2 ± 10.3 to 324.82 ± 6.7 ms; p < 0.01). Conclusion: Button damperreduced 10% of the racket’s impact force and damping time regardless of string tension, whereas rubber band damperreduced the damping time at low string tension only.