By: Elly Goan and Anika Soitkar
Introduction
In the 2019 NFL season, the Kansas City Chiefs demonstrated the potential power of a bye week. Sitting at 7 wins and 4 losses before their break, the team seemed solid but still had room for improvement. After their week off they returned with renewed intensity, closing out the regular season with five straight victories and carrying that momentum into the playoffs and to the Super Bowl.
So, do bye weeks help teams perform better? Or are stories like the Chiefs’ just exceptions? In this article, we’ll examine the recent 2023-2024 NFL season and analyze how these professional football teams performed in areas like scoring, yards, and injuries before and after their bye week.
Definitions
Before breaking down the data, we will first define some important terms:
Bye week: one scheduled week during the regular season in which a team plays no games
Injury report: document with the health status of players leading up to a game
Scoring margin: the difference between the number of points a team scores and the points their opponent scores
Win/loss rates: team's success over multiple games, calculated by dividing the number of games won by the total number of games played
Offensive yards: total yards (passing and rushing) a team gains on offense
Defensive yards: total yards a team’s defense allows the opposing offense to gain
Rushing yards: total yards gained by a teams offensive through running the ball (passing is not considered)
Time of possession: the total amount of time a team controls the ball
Penalty yards: the number of yards a team loses as a result of committing penalties
The Data
Injury Report
This data compares the number of players on each team’s injury report before and after their bye week. Most teams, including the Houston Texans, Arizona Cardinals, and the Los Angeles Rams, have noticeably fewer players on their injury report after their bye week, suggesting that the bye week typically allows players to recover, reducing the number of injuries in upcoming games. Only one team, the Chicago Bears, had no difference between the pre-bye and post-bye injury counts, indicating their bye weeks may not have significantly impacted their injury recovery. This lack of change might be due to having minimal injuries heading into the bye week or the timing of their bye not aligning with when players needed the most rest.
Interestingly, the Philadelphia Eagles and Atlanta Falcons saw an increase in the number of players on their injury report after their bye week. This shows that while bye weeks provide rest, they don't necessarily prevent injuries from accumulating as the season progresses. For players who may have been managing minor injuries, returning to practices could inadvertently worsen their condition. Some players might develop soreness or other symptoms after the last pre-bye game, only to be added to the injury report during or after the bye week.
Overall, while the majority of teams benefit from the break with reduced injuries, however the varied outcomes convey that a bye week is not a guaranteed solution for recovery. Factors such as the timing of the bye week, the severity of pre-existing injuries, and the intensity of practices all play a role in shaping a team's health status.
Win Percentage Rate
This graph demonstrates the NFL teams’ average win rate before their bye week in an average percentage which are graphed by the blue line. The red line reflects the win percentage of the team in their first game following their bye week. In this case, the win percentage can only be demonstrated by 100% or 0% because it was a measure of one game.
This graph has found that 11 out of 32 teams within the NFL league lost after having a bye week. The distribution of the graph demonstrates there is a lack of correlation between which teams won and lost following the bye week. The three teams with the lowest win rate going into their week won following the bye but so did the team with the highest win rate.
Since this graph lacks evidence that the extra time to rest, prepare, and practice is a strong factor in leading to win after a bye week it leads to consideration of other factors. It would be helpful to question the strength of the team played following the bye week and even the strength of teams previous to the bye week. Leading into the season there are expert NFL analyses that can even argue that teams may do well just based on strength of schedule.
Offensive Yards
Professional NFL analysts debate whether a strong offense or a strong defense is the key component to winning games. Both are arguably important to maintain a high score for themselves and a low score for their opponents.
This graph demonstrates each teams’ average offensive yards before the bye week and then the number of offensive plays in their first game following their bye week. There is large variability demonstrated in the graph as there are 11 out of a total of 32 teams that observed an increase in yards following their bye week. Given this almost half-and-half split finding it can be seen that the prolonged time between games does not have a significant impact on whether a team will continue to put up more offensive yards.
Defensive Yards Allowed
On the other hand, this graph represents the total defensive yards allowed as an average before the bye week and the one game following the bye. Similarly to offensive yards gained, this graph finds that 17 out of the 32 total teams experienced a decrease in yards allowed by their opposing team. A decreasing number is good in this situation, opposite of offensive yards, as this means the team was able to defensively stop the offensive of their opponent. With only 17 teams experiencing a better performance on defense overall it can be found that there is no significance with the extra time to prepare and rest for a team’s overall defensive performance.
Rushing Yards
This graph compares the average rushing yards of the NFL teams before and after their bye week. Out of 32 teams, 12 teams had more rushing yards, 18 teams had fewer rushing yards, and 2 teams had approximately the same yards in the game following their bye week. Once again there is no consistent pattern in this data, so the varied outcomes imply that bye weeks do not have a significant effect on the teams’ rushing yards before and after the bye week.
Time of Possession
This graph displays the average time of possession of NFL teams before and after their bye week. While 13 teams had an increase and 19 teams had a decrease in time of possession, there is very little difference in the time of possession, as all of the statistics demonstrated in the graph are approximately similar. All the teams show minimal variation, with the bars being nearly the same length. This suggests that bye weeks have a negligible impact on teams' time of possession in games.
Conclusion
In conclusion, it seems as though a bye week in the NFL league is not a key factor in team performance. As analyzed throughout the 2022-23 season there was a lack of correlation in offensive yards, defensive yards allowed, rushing yards, and time of possession. In football, these are all important factors and key to maximizing winning games. There was observed large variability and typically about an even split between improvement and worsening statistics for teams. Given all these findings the only statistics that observed a strong benefit from the bye week was the number of players on the injury report. There was a strong decrease in the number of players on the report for each NFL team. This seems expected as the bye week provides the player two weeks to recover in opposition to the typical one week. Given this, it was surprising to see the lack of other increases in performance as it is proven that each team is now more healthy.
Overall, it is found that rest time is very important in allowing athletes to recover. However, just having more rest time does not necessarily indicate that the team will perform better overall. The highly praised bye week rest from NFL analysts may need to be looked at more closely as there is no strong correlation from the more recent season that indicates that a bye week is not a key factor for a team’s overall performance.