Operating in Complexity: Applying Military Strategy to Sports Medicine

Australia’s Harry Wilson is substituted after sustaining an injury REUTERS/Siphiwe Sibeko

In the realm of sports medicine, there is a growing recognition that injuries do not arise from simple, isolated causes. Instead, they emerge from a dynamic interplay of multiple factors that interact in unpredictable ways. This perspective aligns with the concept of complex systems, a framework increasingly adopted in fields such as ecology, economics, and national security. In 2016, a collaboration of Brazilian and Canadian sport scientists published a seminal article in the British Journal of Sports Medicine, asserting that sports injuries should be understood as emergent phenomena of complex systems rather than the result of linear cause-and-effect chains⁽¹⁾.

A complex system has several key characteristics: numerous interacting elements, emergent behavior, non-linearity, feedback loops, and adaptability. In the context of sports injury, these elements are visible across multiple dimensions. Numerous factors contribute to injury risk—biomechanical, physiological, psychological, and social. These factors do not act in isolation; they interact dynamically. For instance, a footballer’s recent increase in training load might not pose a risk in isolation, but when coupled with poor sleep, emotional stress, and nutritional deficits, the system’s threshold may be exceeded.

Emergent behavior refers to the way a system’s overall output cannot be predicted merely by analyzing its components. An athlete who appears physically robust may still sustain an injury due to unseen psychosocial stressors. Non-linearity means that small changes in one area (like a minor change in running mechanics) can have disproportionately large effects. Feedback loops occur when system outputs feedback into the system as inputs—consider how fear of re-injury affects movement patterns, which in turn may predispose the athlete to another injury. Finally, adaptability speaks to the dynamic nature of athletes and their environments: both are in constant flux, adjusting to internal and external stimuli.

Given this complexity, it is no surprise that traditional injury prevention strategies often fall short. Most existing programs are predicated on linear models: identify a risk factor, apply an intervention, expect a predictable result. However, if injuries are emergent properties of complex systems, then controlling for one factor may have minimal or unpredictable effects. The Brazilian and Canadian research team note that "We should not seek to find a single risk factor, but rather understand how multiple factors interact to create conditions for injury."

This challenge is borne out in the data. Recent research in elite football demonstrates that injury numbers continue to continues to rise despite increased investment in injury prevention science⁽²⁾. Specifically, the number of matches missed due to injury has not decreased over the last decade. This suggests that despite a more extensive understanding of risk factors and the proliferation of screening tools and load monitoring technologies, the injury burden remains substantial.

If injury prediction and prevention remain elusive despite decades of research, perhaps it is time to consider how other high-stakes professions deal with complexity and unpredictability. Fields such as aviation, emergency medicine, and the military have long operated in uncertain environments where clear cause-and-effect relationships are rare. These fields have developed tools and strategies for decision-making under conditions of uncertainty, and there may be valuable lessons here for sports injury professionals.

One such concept is VUCA, an acronym first introduced by the U.S. Army War College in 1987 to describe the post-Cold War world⁽³⁾. VUCA stands for Volatility, Uncertainty, Complexity, and Ambiguity (see table 1). Leadership and strategy authors have adopted it to describe environments that are unpredictable, dynamic, and difficult to control. This description applies equally well to the injury landscape in elite sport.

Table 1: VUCA definitions 

To navigate such environments, military strategists have turned to the OODA loop. Developed by U.S. Air Force Colonel John Boyd, the OODA loop is a decision-making cycle composed of four stages: Observe, Orient, Decide, and Act (see figure 1)⁽⁴⁾. This framework is designed to help individuals and teams function effectively in chaotic, high-pressure settings. What makes the OODA loop particularly suited for VUCA environments is its iterative nature. It is not a one-time process but a continuous cycle that allows for rapid adjustment and learning (see figure 2).