Relative Rest Index Correlates To Winning Percentage In 2022 National Football League Season

American football is a popular sport with numerous collisions each game which can hinder subsequent performance. Therefore, adequate rest between games is important. PURPOSE: To assess whether the average relative rest (RR) for a professional football team predicts win percentage (WIN%). METHODS: Each game played in the 2022 NFL season (n = 271) was analyzed as an individual case. Publicly available data was initially downloaded from www.profootballreference.com and spot checked through www.NFL.com. RR was defined as the difference in the number of minutes between the scheduled start of successive games between opponents. During week one, each team was assigned a rest interval of 0, resulting in no difference between opposing teams. Each team’s season average RR was calculated and correlated with their final win percentage (WIN%). Teams were also grouped based on their season average RR into even thirds: HIGH (teams 1-11), MID (teams 12-21) and LOW (teams 22-32). Lastly, teams were separated based on WIN% into teams with a record above 0.500 (WIN) and below 0.500 (LOSE), as well as teams qualifying for the playoffs and those not qualifying for the playoffs. Correlational analysis was completed using a Pearson Product Correlation between RR and WIN%. Additionally, a one-way ANOVA was used to assess differences in WIN% between different RR groups, while an independent samples t-test was used to assess differences in RR between winning and playoff groups. Significance was set at α ≤ 0.05. RESULTS: A significant correlation between WIN% and RR was observed (r = 0.338; r2 = 0.114; p = 0.029), though no statistically significant difference in WIN% was observed (F = 2.162; p = 0.133) between HIGH (0.538 ± 0.214), MID (0.559 ± 0.193) and LOW (0.412 ± 0.108) RR groups. Differences were observed for RR between WIN (0.183 ± 0.487) and LOSE (-0.175 ± 0.476; p = 0.022) as well as between playoff teams (0.206 ± 0.485) and teams not qualifying for the playoffs (-0.153 ± 0.479; p = 0.022). CONCLUSION: These data indicate the season average RR did predict the WIN% throughout the 2022 NFL season and may have accounted for as much as 11% of the variation in WIN%. Future investigations should determine the level to which this relationship may exist historically and if different scheduling practices throughout the history of the NFL may influence these results.