Game Spacing and Density in Relation to the Risk of Injuries in the National Hockey League

Abstract

Background: Ice hockey has significant workload demands. Research of other sports has suggested that decreased rest between games as well as an increased workload may increase the risk of injuries. Purpose: To evaluate whether condensed game schedules increase the frequency and severity of injuries in the National Hockey League (NHL). Study Design: Descriptive epidemiology study. Methods: Data were obtained from publicly available online sources on game schedules and injuries for all NHL teams for the 2005-2006 through 2018-2019 seasons. Injury rates (per team per game) and the proportion of severe and nonsevere injuries were determined. The game-spacing analysis assessed the risk of injuries in relation to the number of days between games played (range, 0-≥6 days). The game-density analysis assessed the risk of injuries in relation to the number of games played within 7 days (range, 1-5 games). Results were assessed by analysis of variance, the post hoc Tukey test, and the chi-square test of distribution. Results: The game-spacing analysis included 33,170 games and 7224 injuries, and a significant group difference was found ( P = 1.44×10–5), with the post hoc test demonstrating an increased risk of injuries when games were spaced with <1 day of rest. There was no significant difference in the ratio of severe to nonsevere injuries. The game-density analysis included 33,592 games and 10,752 injuries, and a significant group difference was found ( P = 8.22×10–48), demonstrating an increased risk of injuries with an increased number of games in all conditions except for the comparison between 4 versus 5 games in 7 days. There was also a significant difference in injury severity ( P = .008), indicating that the least dense condition had a higher ratio of severe to nonsevere injuries compared with the other game-density conditions. Finally, the game-density analysis was repeated after excluding games played with <1 day of rest, and the finding of increased injury rates with increasingly condensed schedules remained significant ( P = 9.52×10–46), with significant differences between all groups except for the comparison between 1 versus 2 games in 7 days. Conclusion: We found that a condensed schedule and <1 day of rest between games were associated with an increased rate of injuries in the NHL. These findings may help in the design of future game schedules.

The Effects of Modified Game Schedules on Injury Rates in the National Hockey League (NHL)

“…The 2019-2020 playoffs had an extraordinarily high number of exposures per week with less recovery time between games. Decreases in game spacing have previously been proven to increase the risk of injury in the NHL [ 17 ]. Additionally, because we found a significant correlation between playoff density and injury, it is likely that the condensed schedule played a part in the increased injury rate during the 2019-20 playoffs.…”

Association of Injury Rates Among Players in the National Football League With Playoff Qualification, Travel Distance, Game Timing, and the Addition of Another Game: Data From the 2017 to 2022 Seasons

“…However, they do not align with studies of the National Hockey League (NHL) and National Basketball Association (NBA), which found an increased risk of injury with schedule condensation and away games on consecutive days, respectively. 5 , 27 This underscores the unique nature of the NFL schedule among American team sports, in which teams invariably play 1 game per week, half of which are at home, and therefore travel a maximum of once per week for half of the season. In contrast, an NBA or NHL team may play on consecutive days and multiple times per week in different cities.…”

“…The aim of the current study was to determine the relationship between scheduling factors and injury rates among professional athletes in the NFL. Based on the results of previous studies among other professional sports, 5 , 27 we hypothesized that higher cumulative travel distance, playing overseas games, having a bye week earlier in the season, and an expansion of the regular season would be associated with higher injury rates.…”

The recovery of muscle function and glycogen levels following game‐play in young elite male ice hockey players

“…In the National Hockey League, it is for example normal routine to compete in four games weekly, spending large amounts of time traveling and leaving limited time to restore physiological homeostasis, which may increase the predisposition to injuries and lead to performance deteriorations. 8 It has previously been demonstrated that muscle force production in university level ice hockey players is impaired by up to 30% during a weekly cycle of games and training. 9 In particular, the force production obtained by low-frequency (20 Hz) electrical stimulation of the muscle surface was reduced postexercise and during recovery, a common phenomenon determined "prolonged lowfrequency force depression".…”

“…This is highly relevant in modern elite ice hockey as players endure tightly congested in‐season game schedules and during cup tournaments, where games are often played on consecutive days interspersed with less than 24 h of recovery. In the National Hockey League, it is for example normal routine to compete in four games weekly, spending large amounts of time traveling and leaving limited time to restore physiological homeostasis, which may increase the predisposition to injuries and lead to performance deteriorations 8 …”