Recently, Anterior Cruciate Ligament (ACL) injuries in female football players have surged, gaining the attention of health and performance staff. The multifactorial model of injury causation highlights various risk factors like training load, strength, match schedule, female anatomy, and hormonal influences (Pfeifer, 2018). Nonetheless, the interaction among the athlete, playing surface, and shoe type often goes unnoticed but is a crucial determinant in this scenario. This triad engenders a complex interplay significantly affecting the risk of ACL injuries.
An important problem factor may lie in the shoe-surface interaction, particularly revolving around the concept of rotational traction. Rotational traction is the force that allows a player to make sharp turns or change direction quickly on the playing surface. Adequate levels of rotational traction are required for performance as they enable better grip and agility. However, at excessive levels, they also come with an increased risk of lower limb injuries, such as ACL tears. This is especially the case when the foot is firmly planted on the ground, and the player makes a sudden directional change, creating a twisting force on the knee that can potentially cause an ACL tear.
One study found that peak rotational traction differed significantly across shoe models, shoe outsole groups, and grass species, indicating that the choice of footwear and the type of playing surface significantly affect the level of rotational traction experienced by players (Thomson et al., 2019). A previous study emphasized that higher levels of rotational traction are associated with a doubled risk of lower limb injury, underscoring the importance of this factor in the overall aetiology of ACL injuries in football players (Thomson et al., 2015). Moreover, as football footwear and pitch designs continue to evolve, ongoing evaluations of their performance under simulated loading conditions are essential to ensure that player performance needs are met while minimising injury risk (Villwock et al., 2009).
The design of football boots and the pitch condition are substantial factors herein, The interaction between the player, shoe, and surface is dynamic, with each element impacting the others. For instance, a boot design that amplifies rotational traction could escalate the risk of ACL injuries, especially on a surface that already promotes high traction levels. Conversely, a well-maintained pitch with a surface engineered to minimise excessive rotational traction can act as a safeguard, diminishing the risk of such injuries. In this player-shoe-surface interaction, the rotational traction can be managed in two ways.
Firstly, firms like Ida Sports and Nike are now fashioning football boots to cater to the unique biomechanics of female athletes. Ida Sports aims to provide a comfortable fit for women, eliminating the need for extra adjustments like tape and straps. Nike, with its Phantom Luna boot, developed with female players at the heart of the design process, reflects a growing awareness and a proactive step towards alleviating ACL injuries through specialised boot designs offering differing rotational traction compared to men’s football boot designs.
Secondly, appropriate pitch maintenance strategies can modulate the rotational traction of a pitch, beginning with understanding the pitch’s rotational traction values. Raw Stadia aspires to quantify and analyse pitch characteristics using innovative technology such as the rotational traction tester, thereby offering objective insights into the pitch’s impact on players and contributing to the comprehension and addressing of the various factors affecting the health and performance of football players.
In conclusion, the multifactorial model of ACL injury risk factors in female football necessitates a comprehensive approach to mitigate this pressing issue. Delving into the player-shoe-surface interaction by grasping the implications of rotational traction on injury risk is pivotal for formulating effective preventive strategies, thereby fostering female footballers' long-term health and performance.