Mercedes Sanchis Almenara; Enrique Alcántara Alcover;  Rafael Mengual Ortolá;  Laura Magraner Llavador; Jaime M. Prat Pastor*; Nicolás Palomares Olivares; Mª Sonia Gimeno Peña; Mª Amparo Guerrero Alonso

Instituto de Biomecánica (IBV)
* The IBV Health Technology Group, Bio-engineering, Biomaterials and Nanomedicine CIBER (CIBER-BBN)

Paddle tennis is a relatively new sport and, despite the fact that more and more facilities are being made available to the ever-growing number of lovers of the game, it does not receive the treatment that is meted out to a majority sport. In this context, it is indeed remarkable that no studies have been carried out to identify what properties the surfaces on which the game is played should have. As a result, artificial grass surfaces have been manufactured and installed without anyone knowing whether their properties are suitable from the players’ safety and performance point of view. This article summarizes the work that the Instituto de Biomecánica (IBV) has carried out in order to develop a technical document to regulate the properties of such surfaces. It is currently being reviewed by members of the SC3 of the CTN 147 Technical Committee for Standardization.

INTRODUCTION

Between 2005 and 2010, paddle tennis established itself as one of the 10 most popular sports in Spain. According to the latest survey on sporting habits carried out by García Ferrando in 2011, the percentage of population that plays paddle tennis rose from 0.9% to 2.6% in that period. This phenomenon brought about an increase in the number of available facilities for this sport, with an increase of around 900%, 600% and 300% in the Autonomous Communities of Castilla La Mancha, Extremadura and the Basque Country, respectively. While these are the only Autonomous Communities that carried out a census of their sports facilities in 2005 and 2010, the above leads us to think that there will have been a considerable increase in the rest of the country as well.

As usually happens in young sports such as paddle tennis, industry has led the development of facilities and equipment while knowledge generation has lagged behind. This explains why there are no technical reference documents that determine what properties paddle tennis playing surface should have, which has in turn led to artificial grass surfaces being manufactured and installed without anyone knowing whether their properties are suitable from the players’ safety and performance point of view.

In order to alleviate this deficiency, the IBV has carried out the necessary research work to develop a technical standard on artificial grass surfaces for paddle tennis courts.

In this work, we studied how players and paddle balls interact with the surface, in order to identify the appropriate test methods and to establish reference values. The properties of the sports surface might ensure that it is safe to play paddle tennis, while at the same time ensuring that it is conducive to maximum performance on the part of the players.

The proposal for a technical standard is currently being analyzed by Subcommittee 3 (responsible for ensuring the technical regulation of sport surfaces) of the CTN 147 Technical Committee for Standardization - SPORTS. EQUIPMENT AND SPORT FACILITIES, whose secretariat is the Instituto de Biomecánica (IBV).

Figure 1. Evaluating the interaction between players and the sport surface.

DEVELOPMENT

The research work was carried out in different phases. We first of all identified the movements that players make while playing paddle tennis and that involve interactions between the shoes and the sport surface. We also determined how frequently they hit the ball in order to identify how the ball interacts with the playing surface. In both cases, this work was carried out by watching competitive matches. Subsequently, we analyzed the effect of the identified interactions on the players’ performance and safety.

During the second phase, we selected the regulatory tests that best simulated the most frequent and important players and balls interactions with sport surfaces, in order to analyse the properties of the playing surface. In this way, we developed a test protocol to assess the force reduction, friction and vertical ball rebound on the surfaces of the paddle courts.

Following this protocol, we evaluated several paddle courts that had different types of artificial grass surfaces (registering the fiber length, the number of stitches, the amount of sand infill, etc.). We also sought the players’ perception as to the properties evaluated in each of the courts.

From the obtained results, we established reference values for each of the properties that were validated in the final phase of the study. In this phase, and in the first instance, we sought the opinion of the players after they had played a game on a court that complied with the established values. Subsequently, we obtained their opinion after they had played on another court that did not comply with those values.

Figure 2. Evaluating the players’ opinion.

Afterwards, semi-professional players took part in a controlled circuit that simulated specific movements of paddle tennis. They repeated the circuit three times using three models of paddle shoes that featured different soles, even though all three models are marketed as being suitable for this sport. Finally, we carried out a subjective assessment of the properties of the playing surface and the perception of safety and performance related to its use.

Figure 3. Performing the movements included in the controlled circuit.

The obtained results allowed us to redefine the reference values and to start working on a draft proposal for a technical standard to regulate the properties of artificial turf surfaces for paddle.

CONCLUSIONS

The results of this study have contributed, on the one hand, to the development of the first technical standard that regulates artificial turf surfaces for paddle courts; on the other hand, we have advanced on the knowledge of this sport. It has been established that, taking into account both their frequency and their possible influence on performance and health, the most relevant movements are lateral and front displacements, split-steps and jumps to smash the ball.

It has been identified that players are able to perceive the mechanical properties of the sport surfaces and to relate, for example, the hardness of the court with its capability to reduce the impact forces. Moreover it has been verified that there is a high correlation between players’ subjective assessment of the evaluated properties and their perception of performance and safety.

Figure 4. TRRL pendulum for evaluating friction of the sport surface.

It should also be noted that the study we carried out can serve as a starting point for designing paddle shoes. Footwear with soles that have a lower static friction coefficient and greater rigidity have received the worse valuation by players, both from the point of view of their interaction with sport surfaces and with the perceived performance and safety during their use.

The technical document is currently being reviewed by the SC3 of the CTN 147 SPORTS. EQUIPMENT AND SPORT FACILITIES.

ACKNOWLEDGEMENTS

To the Spanish Paddle Association.