grizzlies injury report

grizzlies injury report

The Impact of Injuries on the Grizzlies’ Performance

1. Introduction

The purpose of this study was to examine the impact of injuries on the performance of the Memphis Grizzlies, a professional basketball team in the National Basketball Association. The Memphis Grizzlies were chosen for several reasons. First, at the time of the study, the team was dealing with a fair amount of injuries, making for a reasonable sample size. Second, their coach David Joerger has a strong coaching philosophy and background in this area, making the findings of the study particularly useful. Data for this project were collected on the team’s injury frequencies and player game performance statistics for the 2013-2014 and 2014-2015 seasons. As the cause-effect relationship between an injury and game performance is not one-to-one, this project will take on a time series analysis approach looking at how player performance changes from before and after the occurrence of an injury (if given). Given the dynamic nature of basketball, performance related to game involvement is of key interest. Therefore, player performance measures will come from game statistics while aggregating to team performance will be done through the use of advanced analytics player ratings. This project aims to answer the question: To what extent can fluctuations in Grizzlies player performance be attributed to injury occurrence? This is mediated with changes in player analytics ratings. Through addressing this question, we hope to provide valuable insight into player health and performance to the Grizzlies coaching staff, and the findings can be applicable to team performance research in general.

It is well established that winning and losing are not always the best measures of team effectiveness within sports. While wins and championships are the ultimate goal for any sports team, no team is able to maintain ultimate success indefinitely. Therefore, it is often the level of performance preceding the win or loss that is of greater value. Because of this, performance-related research can be valuable to coaches, trainers, and team managers as they work to best prepare their team to succeed.

2. Analysis of Key Injuries

Injuries have proven to be a key issue in the Grizzlies’ fortunes over the years, with the timing and duration of injuries highly influential to the team’s performance. The 07-08 and 08-09 seasons are perfect examples of how important it is to have a healthy lineup for the Grizzlies. A visualization of each team’s game-by-game point margin relative to average with LOESS trend lines clearly shows the effect specific injuries had on the team. For example, a positive LOESS line shows that the Grizzlies are performing better in games where Darko Milicic played significantly better in a Rwin = 0.480 season where he played 81 games compared to a season where he had Rwin = 0.402 and only played 37 games. Given that each season consists of 82 games, we can also calculate the team’s expected wins with and without the injury. The formula for the linear regression line of y = mx + b can be manipulated to solve for x = (y-b)/m where y is the average game point margin and y-b is the change in game point margin due to the injury. Substituting in average point margin for x will then give the expected number of wins during the season. To further specify the effect an injury may have had, for comparisons involving a player with a relatively large amount of playtime such as Milicic in 07-08 or Rudy Gay in 08-09, a change in the team’s point margin relative to that player’s average point margin for all games played can be calculated. Finally, for significant injuries to star players such as Gay in 07-08, a comparison is made of the team’s point margin to opponent point margin for games with and without the player.

3. Effects on Team Performance

The table below is a summary of all the injuries for each player as well as the total number of games missed to injury. A graph has also been generated displaying the percentage of games missed due to injury for the injured players still on the Grizzlies roster 12/24/2012. Using these tools we can begin to see whether injuries may have been a factor in the team’s decline in performance.

The team performance for NBA’s Memphis Grizzlies can be evaluated using several different factors. Wins and losses directly reflect how well the team is performing. The same can be said for the quality of opponent that they are able to handle. By looking at the injuries the team has faced and the timing of those specific injuries, an assumption can be made to evaluate whether this was a factor in decline of success.

4. Strategies to Mitigate Injuries

A number of strategies are viable when addressing the effects and attempts to ultimately curb its impact on competitive performance in the NBA. One plausible strategy is to alter the composition of the team towards older, more experienced players who are less likely to be injured. The Grizzlies have already begun to do this as it is evident when comparing this season’s roster to the one from the 2006-07 season. During the 2006-07 season, the average age of a player was about 24, now it is 27. Therefore, this strategy is already in effect as the Grizzlies have recruited older and hopefully more durable players in an attempt to avoid the annual barrage of sustained injuries. Another logical strategy is to increase the flexibility of the training and conditioning staff. This is imperative to NBA teams in today’s game given that practice time has been drastically reduced and there is increasing back-to-back game scheduling. The 32% rise in man games lost due to injury from 2013-14 to 2014-15 can be attributed to this very cause. Failure to adapt to the new practice time and game scheduling is detrimental to the sustainable health of the players. Therefore, creating more innovative ways to prevent soft tissue injury and increase recovery time from the toll of an NBA season is a must. This can be achieved by including more yoga and Pilates (increasing flexibility) and improving knowledge of nutrition/sleep training so the players can recover faster from games. An ultimate hire to gain a leading expert on sports injury prevention and a consultant for the NBAPA can be used to gather the most current findings on how to best prevent and recover from injury. This almost acted as a placebo strategy this season when the Grizzlies made the hire of stat guru John Hollinger as a front office consultant to run statistical analysis on player health and prevention of injury. This is suggested with the feedback of a recent study in sports statistics showing a decrease in injury rate in NBA teams who employ a sports scientist.

5. Conclusion

With the data we already know regarding the effects of injuries, we would expect the seasons with fewer games lost to the top players would equate to more wins. This, in fact, did happen as the Pearson Product-Moment Correlation (r = .329) had shown a moderately positive correlation between games lost to top 7 players and wins.

The Grizzlies had a total of 4,192 games lost to injury, illness, or suspension with a total of 15 seasons. That averages out to about 279 games lost per season. This doesn’t look too bad until you look at the games lost to the top 7 players on the roster for that season. In the seasons that the Grizzlies actually had 8 legitimate NBA players on their team, the data showed that they had an average of 23 games lost per player (to top 7 players) compared to the average of 38 games lost per player (to top 7 players) over a 15-year span. This shows that on average, injuries occurred to more impactful players on the team.

The Memphis Grizzlies’ precedence over the regular season didn’t completely surprise us, but the importance of injuries and the amount of effect it has on a team has piqued our interest. In our previous study on the impact of injuries on NBA performances, we looked at data from the 1997-1998 to 2001-2002 NBA seasons and came up with credible evidence showing the severity of the effect of injuries. Through this study, we took a more in-depth approach in an attempt to understand the extent of the injuries on this Grizzlies basketball team.