The Comeback Curve: How Injury Risks Surge After Return-to-Play in Football

In professional football (soccer), the risk of injury remains a significant concern, particularly for players returning to the field after recovering from an injury. This post delves into the research surrounding the injury risk trajectory after return-to-play (RTP), exploring how different factors like injury severity and playing position influence the likelihood of subsequent injuries.

Key Takeaways:

• Increased Risk Immediately After RTP: The study identifies that players face about twice the risk of non-contact injuries immediately upon returning to play. However, this elevated risk gradually declines, returning to baseline levels within approximately four weeks.

Injury Risk Decline Over Time After Return-to-Play

• The “Hazard Curve” Insight: Using advanced statistical methods like time-to-event analysis and Kaplan–Meier survival functions, researchers plotted a continuous hazard curve to depict injury risk over time. This curve shows that the initial sharp increase in risk gradually decreases, with a “half-life” of around 25 days.

• Impact of Injury Severity: Players recovering from more severe injuries show a delayed peak in their risk of subsequent injury, which is higher and more prolonged than for those returning from milder injuries. This indicates that rehabilitation and RTP protocols should be more conservative for severe injuries to manage the risk effectively.

Injury Risk by Severity of Initial Injury

• Playing Position Matters: Forwards were found to have a unique risk profile compared to other playing positions. Their injury risk tends to fluctuate, unlike goalkeepers, midfielders, and defenders, whose risk steadily declines after RTP. Forwards’ aggressive playing style and the physical demands of their position may explain this phenomenon.

Injury Risk by Football Playing Position After Return-to-Play

Why This Matters for RTP Decision-Making

One of the most important takeaways from this research is its application in RTP decision-making. Coaches, medical staff, and sports scientists can use the findings to adjust player workloads and make more informed decisions based on the player’s recovery status, injury severity, and position. The concept of a “one-month excess risk decay” can help teams determine when players are at lower risk for re-injury and plan their reintegration into full competition accordingly.

Practical Recommendations for Teams

1. Monitor the First Four Weeks: The first month post-RTP should be closely monitored. While the overall injury risk drops after this period, careful observation during the initial weeks can help reduce the likelihood of subsequent injuries.

2. Tailor RTP Protocols by Injury Severity: Players recovering from severe injuries should have individualized RTP protocols that reflect the extended risk window identified in the study.

3. Consider Positional Demands: Special attention should be given to forwards, who may experience more fluctuating injury risk patterns post-RTP. Position-specific recovery plans could minimize risk and optimize performance.

Conclusion

This research contributes to a better understanding of the time course of injury risk following RTP in football. By identifying key patterns in injury risk based on the type of injury and the player’s position, the findings offer valuable insights for more effective injury management and RTP planning in professional football.

Reference

Zhang, G., Brink, M., aus der Fünten, K., Tröß, T., Willeit, P., Meyer, T., Lemmink, K., & Hecksteden, A. (2024). The Time Course of Injury Risk After Return-to-Play in Professional Football (Soccer). Sports Medicine. https://doi.org/10.1007/s40279-024-02103-3