Though it is one of the most important aspects of the coach-athlete relationship, I feel that the term “buy-in” has been overused in recent years, so for the purposes of this article, I will rather use the term “trust”, as essentially this is what we are trying to create as coaches in terms of relationships we engage in with our athletes.

Team sports, including football, have often been described in the context of the complex systems theory, where a complex system is a system composed of many components that interact with each other. It has been adopted by coaches in team sports to move away from a reductionist model of training different physical and tactical elements separately to overloading different physiological and tactical elements of the game through tactical iterations, such as manipulating player numbers and pitch size in small sided games (SSG).

Change of direction (CoD) and cutting ability are an important performance factor in many team sports, although the biomechanical determinants or landmarks are not particularly well understood (Marshall et al., 2014). It is also unclear whether there are clear correlations with strength and power parameters and CoD actions, particularly when seen from the chaotic lens of team sports, when CoD actions are unpredicted and reactive to an external stimulus (Welch et al., 2019).

Rupture of the anterior cruciate ligament (ACL) is one of the most debilitating, yet increasingly common injuries in high-level sports. Mechanically, an ACL rupture occurs when an excessive tension force is applied to the ACL (Yu & Garett, 2007). This normally involves a combination of anterior shear load on the tibia, valgus loading, tibial internal rotation and either small knee flexion angles (0-30°) or large knee flexion angles (90° and more), and angular velocities, respectively, and could be the result of intermuscular coordination (Prodromos, 2007; Hewett et al., 2005).