Autors: Ricard Barberà-Guillem, Rafael Mengual Ortolà, Laura Magraner Llavador, Fernando Gómez Sendra, Begoña Martínez Climent, Juan Carlos González García, Sara Gil Mora

In 2021, when FIFA published its Testing Manual for natural turf pitches as part of its Quality Programme, it laid down a new framework for the quality of natural turf playing surfaces for soccer. This framework was completed in May 2022 when it published the reference values that pitches must meet in terms of the various parameters established for their evaluation. 

The Instituto de Biomecánica (IBV) has been involved in this new performance framework. In September 2022, when FIFA organized the first round-robin for the accreditation of laboratories, the IBV was awarded its first accreditation as a natural turf testing center. This accreditation, which was recently renewed in Granada, means that the IBV is now one of the world’s leading natural turf testing centers.

As a result, the IBV is currently the only center in Spain that is accredited to certify natural turf pitches, in accordance with the FIFA Quality Programme. Having just embarked on the lengthy preparations for the 2030 World Cup, where the playing surface will be the “center stage”, the IBV is ready to certify that the turf will be in top condition.

INTRODUCTION

The gradual introduction of artificial turf playing fields, which began in the 1960s, led to the parallel development of a specific framework of regulations and best practices for this type of facility, particularly in recent decades and since this type of surface began to be used in official competitions at various levels, led by international bodies such as FIFA and ISO, but also here in Spain by the National Sports Council (Consejo Superior de Deportes) and the Technical Committee for the Standardization of Sports Equipment and Facilities (CTN 147)^1,2.

The Natural Turf Quality Manual for Soccer Playing Surfaces came later, perhaps due to the fact that natural turf pitches had an entry level quality mark per se or, perhaps, because different national soccer federations had their own quality manuals or, even, maintenance criteria derived from the personal experience of the greenkeepers of specific clubs. In any case, the aim is the same as for artificial turf: to standardize and clarify the criteria used to ensure the quality of the playing surface, while at the same time guaranteeing the safety of the players. In 2021, FIFA therefore launched its Quality Programme and Testing Manual for natural turf pitches in collaboration with technical staff and sports federations, and in 2022 it published the reference values that pitches must meet in terms of the various parameters assessed in order to be considered suitable and safe playing surfaces.

A review of the sports press over the past year shows that it is all too easy to find complaints about the condition of pitches. Although Xavi Hernández, the coach of FC Barcelona, has made the most headlines for his comments about the poor condition of the pitches his team has played on^6,7, he is by no means the only coach to blame a bad result on the poor state of the pitch. Carlo Ancelotti, the Real Madrid coach, was also very vocal in his criticism when his team were put through the mill by CP Cacereño in the King’s Cup (Copa del Rey) at the Prince Philip Stadium in Caceres⁸. The fact is that no competition has been immune to criticism over the poor condition of its pitches: the Europa League, the King’s Cup and La Liga abound with headlines about matches played on poor pitches. The poor condition of the pitch also made the news in the Women’s Professional Soccer League (La Liga F), following one of this season’s opening matches between Madrid CFF and Barcelona Femenino at the Fernando Torres Stadium in Fuenlabrada⁹.

DEVELOPMENT

The FIFA Quality Programme: types of assessment and aspects to be assessed

Just like the existing FIFA Quality Programme for artificial turf surfaces, the FIFA Quality Programme for natural turf surfaces provides an objective and standardized testing procedure and reporting format that allows clubs and competition organizers to compare the quality of natural turf pitches using the same criteria. The programme proposes two sets of on-site tests, a comprehensive one and a reduced one.

The comprehensive assessment is designed to enable FIFA-accredited test centers to assess the performance of a new or an existing pitch or prior to the staging of a tournament. It includes the evaluation of agronomic behavior and player safety, as well as performance, which is defined as the dual interaction of the surface with the player and the ball.

The FIFA Quality Programme also offers a reduced testing protocol specifically designed for grounds maintenance staff. These tests are more focused on agronomics and can be carried out on a regular basis. They provide guidelines for day-to-day maintenance work, whereas the comprehensive testing protocol must be carried out by FIFA-accredited testing centers and will most probably be carried out only a few times a year.

Figure 2 identifies the points determined by the FIFA Quality Programme where the different values should be analyzed and Table 2 lists the different assessment characteristics grouped under biomechanical and performance characteristics and agronomic characteristics, also differentiating between comprehensive and reduced assessment.

Figure 1. Playing field analysis positions

Table 1. FIFA natural turf assessment criteria

The test criteria have been developed with the symbiosis of agronomic and biomechanical requirements in mind, to provide a safe and high-performance surface. The test protocol does this by requiring test centers to carry out a technical assessment to measure the hardness, stability and evenness of the surface, as well as additional ball-surface interaction tests to validate the overall performance of the pitch. A set of agronomic tests must also be carried out. These tests are particularly important in the case of natural playing surfaces, as only when taken as a whole will they provide insight into the health of the playing surface and the performance that can be expected. The parameters measured when testing natural turf pitches always include ambient temperature and humidity, as well as wind speed and soil temperature.

Each assessable characteristic is given a value on a scale ranging from ‘unacceptable quality’ to ‘excellent quality’. Characteristics with the lowest value on this scale (unacceptable quality) are assigned one point, while those with the highest value are assigned ten points. Some of these values may apply specifically to warm or cold climate grasses (all/warm/cold). Each variable is also given an importance coefficient ranging from 10 to 0.5.

The overall score is obtained by the following calculation:

Table 2 provides examples of the specific ranges for different ratings for a number of variables. The rating ranges may vary depending on whether the grass is for warm or cold environments (thatch depth) or whether it is natural turf or a hybrid or reinforced carpet (root depth).

Table 2. Examples of the assessment of various parameters

The importance of natural turf quality

The playing surface at a soccer match is the “center stage” on which all the action takes place. It must be in the best possible condition to ensure a safe environment that allows players to perform to the best of their ability. With this in mind, FIFA has established a new quality programme for natural turf pitches, in order to “harmonize testing and provide competition organizers with standardized criteria against which to compare the quality of natural playing surfaces”.

In professional soccer, the importance of the quality of the playing surface goes far beyond the players’ experience on the pitch. The condition of the turf also affects the experience of TV viewers, and therefore the overall image of the competition. Therefore, ensuring that the playing surface meets stringent standards not only benefits those directly involved, but also helps to ensure that soccer is presented in a positive light in the media.

Generally speaking, we say that a pitch is in good condition for soccer if it has: (1) an adequate slope, free of potholes and gaps; (2) an effective drainage system; (3) a good ground coverage of desirable species; (4) firmness and stability to provide good playing characteristics; and (5) adequate and clearly pitch markings.

While the increasing awareness of the importance of excellent playing surfaces has led clubs and competition organizers to strive even harder to ensure that they are maintained at a level of excellence, natural turf soccer pitches often face a number of problems, including: (1) unevenness and deficiencies in drainage, which can lead to a loss of plant cover; (2) poor turf establishment, including weed invasion, which affects consistency, pitch appearance and playing quality; (3) inefficient irrigation systems, with poor sprinkler overlap or uneven irrigation, which can lead to heat stress and the onset of disease, affecting turf density and ultimately, turf performance; (4) uneven fertilizer application leading to poor appearance and uneven turf growth; or (5) the presence of overused areas with deteriorated surfaces, often in the goal areas.

The tests proposed by FIFA are already required for official FIFA competitions, including the World Cup, and this requirement may eventually be extended to other competitions. In any case, the proposed tests - which can be applied to any natural surface used for soccer - provide a good tool or best practice manual with which to correct aspects of the installation that can be improved.

CONCLUSIONS

In 2021, when FIFA published its testing manual outlining the methods to be used to assess natural turf pitches as part of its Quality Programme, it laid down a new framework for understanding the quality of natural turf playing surfaces for soccer. This framework was completed in May 2022 when it published the reference values for determining whether a natural turf surface is fit for purpose.

The Instituto de Biomecánica (IBV), as a reference center for sport technology in Spain, has been involved in these developments. In September 2022, when FIFA organized the first round-robin for the accreditation of laboratories, the IBV was designated as an accredited center. This accreditation, which was recently renewed in Granada during the last round robin organized by FIFA, means that the IBV is now one of the world’s leading natural turf testing centers and the only one in Spain with this accreditation, in accordance with the FIFA Quality Programme.

The playing surface will be the “center stage” on which the 2030 World Cup will be played and the IBV is ready to certify that it is in the best possible condition in terms of match performance, player safety and spectator experience, whether they are in the stadiums or watching the World Cup on TV or streaming.

BIBLIOGRAPHY AND REFERENCES

1. Mengual Ortolà R, Magraner Llavador L, Martínez Climent B, Barberà-Guillem R, Alcántara Alcover E. El césped artificial en instalaciones deportivas municipales. De la licitación al mantenimiento. Rev Biomecánica. 2020;(67):38-46.
2. Mengual Ortolà R, Magraner Llavador L, Martínez Climent B, Barberà-Guillem R, Alcántara Alcover E. Ensayos de césped artificial o cómo licitar y mantener una instalación deportiva municipal en condiciones óptimas. Biomecánicamente. Published April 1, 2021. Accessed October 11, 2023. https://www.biomecanicamente.org/news/ibv/item/2043-ensayos-cesped-artificial.html
3. 20 Minutos. Europa pide la eliminación de los campos de césped artificial en ocho años. 20 Minutos. https://www.20minutos.es/deportes/noticia/5181587/0/europa-pide-eliminacion-los-campos-cesped-artificial-ocho-anos/. Published October 15, 2023. Accessed October 16, 2023.
4. Interempresas. Primer campo de fútbol de césped artificial con medidas para evitar la liberación de microplásticos. Interempresas. https://www.interempresas.net/Plastico/Articulos/389535-Primer-campo-futbol-cesped-artificial-medidas-para-evitar-liberacion-microplasticos.html. Published May 23, 2022. Accessed October 16, 2023.
5. Mengual Ortolà R, Barberà-Guillem R, Magraner Llavador L, Martínez Climent B, González García JC, Gil S. Eyeturf, innovación en el mantenimiento de campos de hierba artificial. Portal Piscinas e Instalaciones Deportivas Hoy. Published July 31, 2023. Accessed October 11, 2023. https://portalhoy.es/eyeturf-innovacion-en-el-mantenimiento-de-campos-de-hierba-artificial/
6. Redacción Marca. FC Barcelona. Xavi vuelve a quejarse del césped: “No rodaba bien el balón”. Marca. https://www.marca.com/futbol/barcelona/2022/04/08/624fef00268e3e16408b45b5.html. Published April 8, 2022. Accessed October 11, 2023.
7. Europa Press Deportes. Xavi: “Es un punto más en un campo difícil, el césped nos ha perjudicado.” EuropaPress. https://www.europapress.es/deportes/futbol-00162/noticia-xavi-punto-mas-campo-dificil-cesped-nos-perjudicado-20230416194244.html. Published April 16, 2023. Accessed October 10, 2023.
8. Corbella E. El entrenador del Cacereño responde a Ancelotti por la polémica del césped: “Ya es mayor y jugó en campos peores.” Marca. https://www.marca.com/futbol/copa-rey/2023/01/04/63b50dea22601ddf118b45ec.html. Published January 5, 2023. Accessed October 16, 2023.
9. Concejo Madrid E. Liga F. Victoria blaugrana en medio del ruido. La Vanguardia. https://www.lavanguardia.com/deportes/futbol-femenino/20230916/9232369/victoria-medio-ruido.html. Published September 16, 2023. Accessed October 11, 2023.

AUTHOR'S AFFILIATION

Instituto de Biomecánica de Valencia
Universitat Politècnica de València
Edificio 9C. Camino de Vera s/n
(46022) Valencia. Spain