Predicting the Scale of Tennis Rackets for Optimal Striking from Body Dimensions

Abstract

This study tested the hypothesis that scaling environmental objects can afford differently sized individuals the opportunity to make similarly effective movements with that object. Four similar tennis rackets were scaled to provide consistent differences in length, weight, and grip size. Children between 4 and 10 years of age were asked to strike with each racket for speed and accuracy. A significant relationship existed between body size and strength and the ability to both generate racket head speed and control the racket for an accurate strike; racket size and weight, however, were not significant factors in the ability to swing effectively.

Scaling the Equipment and Play Area in Children’s Sport to improve Motor Skill Acquisition: A Systematic Review

“…compared with a standard ball and a full-size racquet Kachel et al [ 26 ] Ball compression 9–10 years, skilled Y When using the low compression ball (75 % of standard ball, “green”), as opposed to the standard ball, children played more balls at a comfortable height, approached the net on more occasions and had faster rallies Lee et al [ 27 ] Net height, target area, court size 9–10 years, beginners Y Constantly modifying the net height, target areas and court size to create a variable practice environment led to children displaying a greater number of movement clusters c following 4 weeks of practice (600 forehands) compared with children who practiced repetitive drills with the same net height, target areas and court size Larson and Guggenheimer[ 28 ] Ball compression and court size 7–9 years, intermediate Y Skills test performance was better when using a low compression ball (75 % of standard ball) d on a scaled court compared with when using a standard ball on a full-size court Farrow and Reid [ 29 ] Ball compression and court size 8 years, beginners Y Practicing on a full-size court with a standard ball resulted in negative learning relative to practice on a scaled court and/or with a low compression ball (<50 % of standard ball, “red”) e after 5 × 30-min practice sessions. The court had a greater influence on learning than the ball Hammond and Smith [ 7 ] Ball compression 5–11 years, beginners N No differences in tennis skills tests were present between a group practicing with a low compression ball (25 % of standard ball, “red”) f and group practicing with a standard ball following 8 × 60-min practice sessions Gagen et al [ 30 ] Racquet length 4–10 years, beginners N Although every child had one racquet that they swung better than others, the characteristics of this racquet were not related to the child’s size or strength ...…”

“…An interesting question is whether it is possible to quantify the amount of scaling required for each child, to allow desirable movement patterns to emerge. Gagen et al [ 30 ] examined 4- to 10-year-old children who were required to perform a forehand hitting task in which they were instructed to “swing as hard as possible and hit the ball as closely to the centre of the racquet” as they could. Children performed this task using four different racquets that varied in length and mass.…”

“…Children performed this task using four different racquets that varied in length and mass. Gagen et al [ 30 ] anticipated that the unique physical characteristics of each child (hand size, arm length, height, weight, functional leg length, grip strength, shoulder strength) would predict which racquet produced the most desirable performance, as measured by racquet-head speed and accuracy of contact on the racquet. The results showed that for each child one specific racquet produced better speed and accuracy than the other racquets; however, physical characteristics did not predict this ‘optimal’ racquet statistically.…”

“…Additionally, a challenge for researchers measuring skill is to design tests that are well controlled and ecologically valid; however, these two factors are often difficult to reconcile. For example, tennis studies have typically required children to strike an incoming ball of controlled velocity and trajectory (e.g., via an underarm throw or a ball machine) as a measure of their competence [ 24 , 25 , 30 , 31 ]. The assumption is that children who display better performance at this task will also perform better during match conditions.…”

A review of tennis racket performance parameters

“…Other examples of the interaction of racket mechanical characteristics with player biomechanics are skills test performance measures taken when using rackets of different sizes and masses. Gagen et al, [91] reported that based on the speed and accuracy of developing players' (4 -10 years old) strokes using different rackets, there tended to be a 'best' racket for each child. It is possible that the combination of many stroke biomechanics, development, and learning parameters means that it will be difficult to optimise racket inertial parameters.…”