Rethinking Hamstring Injuries: A Call to Address the Root Causes

Hamstring injuries have long plagued athletes across various sports, from elite professionals to recreational players. But what if we’re focusing on the wrong problem? What if hamstring injuries are not the problem themselves but rather the result of deeper, systemic issues?

To illustrate this, consider the concept of survivorship bias—a cognitive trap that distorts how we analyze data. During World War II, researchers examined damage patterns on aircraft that returned from missions. The most bullet holes were found in the wings and fuselage, leading them to suggest reinforcing these areas. However, statistician Abraham Wald challenged this logic. He argued that the damage on surviving planes was misleading; aircraft fatally hit in critical areas—like engines, cockpits, and control systems—never made it back. Reinforcements, therefore, needed to address undetected vulnerabilities, not the areas that survived.

In sports, our collective response to hamstring injuries often mirrors this flawed reasoning. Despite pouring billions of dollars into injury prevention strategies, technologies, and interventions, the results have been underwhelming. Recent data from UEFA reveals that hamstring injuries have skyrocketed since 2016, even with increased attention and investment. This misstep stems from what can be termed injury bias—a tendency to focus on the injured tissue itself rather than the deeper biomechanical and systemic issues that caused the injury in the first place. Much like survivorship bias, injury bias shifts attention away from the true problem and directs resources to treating symptoms rather than root causes.

Survivorship Bias vs. Injury Bias: A Comparative Insight

Both survivorship bias and injury bias highlight how misinterpretation of evidence can lead to flawed conclusions. Survivorship bias stems from analyzing only the data that survives a process, ignoring the critical failures that don’t make it through. In the case of injury bias, the focus is on the tissue that becomes injured, overlooking the broader context of why that tissue failed in the first place.

For instance, the hamstring is often seen as the "problem" because it’s the tissue that fails during high-intensity athletic movements. However, this perspective is akin to reinforcing the bullet-riddled wings of surviving planes while ignoring vulnerabilities in critical systems. The real issue lies in the forces acting on the hamstring due to inefficiencies elsewhere in the body—such as weak core stability or inadequate hip and spine support. These inefficiencies force the hamstring to take on a disproportionate load, ultimately leading to injury.

By treating the injured hamstring as the root cause, practitioners risk neglecting the underlying biomechanical failures. This misdiagnosis not only limits effective prevention but may also increase the likelihood of reinjury, as the systemic weaknesses remain unaddressed.

The Real Problem: Force Dynamics and Biomechanical Stress

Hamstring injuries don’t occur in isolation. They’re a byproduct of the immense forces the human body encounters during athletic movements—particularly change-of-direction events and deceleration. These high-risk actions impose unique demands on the musculoskeletal system, especially when considering the relationship between the upper and lower body.

Here’s a key insight: during change-of-direction events, the upper body experiences twice the velocity typically measured. For instance, if an athlete is running at 20 mph, their upper body is subject to forces associated with 40 mph. Simultaneously, the foot on the ground momentarily experiences a net velocity of zero, creating an extreme mechanical demand. This sharp contrast in velocities produces a cascade of forces that must be absorbed, transmitted, and controlled across the body.

However, injury bias often leads us to misinterpret the role of the hamstrings in these scenarios. Because the hamstring is the tissue that fails, we assume it is the problem. In reality, the hamstrings are often overburdened because they are compensating for weaknesses elsewhere in the kinetic chain. The issue lies in the inability of other muscles, particularly those supporting the hip, core, spine, and skull, to manage the twice-magnitude inertial forces generated during rapid deceleration and directional changes. The hamstring is forced to do too much, leading to injury.

Where Do We Go From Here?

To effectively reduce hamstring injuries, we need to address root causes rather than symptoms. This requires a paradigm shift:

• Rethinking Training Paradigms: Traditional strength training often fails to replicate the high-velocity, multi-directional forces encountered in sport. A more integrative approach that prepares athletes for these demands is essential.

• Emphasizing Whole-Body Isometric Strength: Isometric strength training—actively driving against immovable restraints—can play a pivotal role in fortifying the musculoskeletal system. By developing whole-body isometric strength, athletes are better equipped to handle the explosive demands of deceleration and directional changes.

• Holistic Force Management: Strength and conditioning programs must emphasize how the entire body interacts during athletic movements, accounting for the interplay of upper-body momentum, core stability, and lower-limb biomechanics.

• Data-Driven Insights: To truly understand and prevent injuries, we need precise, actionable data on the forces generated by individual muscles and the mechanisms of injury. Current methods measuring force data often rely on functionally irrelevant gross data, particularly regarding the hamstrings, neglecting the contributions of the nine muscles involved in knee flexion/eccentric knee extension. This narrow focus ignores the interconnected nature of the body and fails to address the root causes of injury and overlooks the total force contributions of individual muscle to the total output.

Even more concerning is that these flawed methods can misinform sports scientists and medical professionals, resulting in misdiagnoses and increasing injury risk. The sharp rise in injuries since 2016 suggests that misleading data is a significant contributing factor. Instead of mitigating risk, these outdated approaches often reinforce incorrect assumptions and overlook key vulnerabilities.

Conclusion

Hamstring injuries are not merely a localized problem; they signal deeper biomechanical and systemic challenges. Much like the lessons from survivorship bias, we must look beyond the obvious and address vulnerabilities previously ignored. Similarly, injury bias perpetuates the misconception that the injured tissue is the problem, rather than a symptom of inefficient force distribution and unaddressed weaknesses in the kinetic chain.

To break this cycle, we need to shift our focus to the whole-body demands of athletic performance and address the root causes. By doing so, we can develop more effective strategies to reduce injuries, protect athletes, and unlock their full potential.

At Isophit, we help the world’s strongest, fastest, and most gifted athletes—and everyday people—win more, hurt less, and age stronger.