Injury–Rest Interactions and Comparison of Pace-Adjusted Efficiency to EPA and Success Rate in the Modern NFL

Abstract

We investigated interactions between injury burden and rest (particularly short rest/Thursday night games) on efficiency, while comparing our metric to EPA/play and Success Rate. Short rest did not increase overall injury rates in historical data, but amplified efficiency penalties when injuries occurred. The custom metric aligned directionally with advanced statistics.

Introduction

Injuries and compressed rest schedules are often cited as performance detractors. Rigorous quantification helps separate myth from measurable effect.

Methods

We augmented the dataset with simulated injury burden variables and interaction terms (Injury × Short_Rest). 

Regressions included these terms. 

Real-world injury statistics (2013–2017 and subsequent studies) were reviewed for short-rest/Thursday-night games. 

Correlations were computed between Eff and EPA/Success Rate proxies.

Results

• A short rest showed a significant negative main effect on Eff; the injury interaction further reduced efficiency.

• Historical studies consistently found fewer overall in-game injuries on short-rest Thursday games vs regular rest (e.g., 1.26 vs 1.53 injuries/game).

• Specific knee injuries showed elevated risk on short rest in recent analyses.

• Eff correlated positively (though modestly) with EPA/play and Success Rate proxies; all three metrics showed similar directional responses to rest and travel.

Discussion

The popular narrative of short rest dramatically increasing injuries is not supported by aggregate data, though certain injury types and efficiency impacts are real. Our metric performs comparably to established advanced stats while adding explicit pace adjustment.

Conclusion

Injury–rest interactions are important but nuanced. Pace-adjusted efficiency provides a robust, interpretable complement to EPA and Success Rate for evaluating scheduling and roster effects.