Does Injury Availability Affect your Team’s Chance of Success?

It has long been suggested that injury rates and player availability affect a team’s chance of success. Let's explore this narrative using sporting examples and the sports science research.

Premier League Injury Rates

Firstly, there are a number of anecdotal examples of this relationship.  The last two Premier League Champions, Leicester City (2015/16) and Chelsea (2016/17), were first and second respectively in Physio Room’s league table for total days lost to injury.

While we should acknowledge the potential limitations of publicly available injury data, I believe it is still worthwhile information and an important trend.

Would Leicester still have achieved the most incredible season in football, infamously overcoming odds of 5000/1, if Kante, Mahrez or Vardy had suffered more injuries?  Would Chelsea have taken their crown if Kante (common denominator!), Costa or Azpilicueta (who played every minute last season) were less available to play?

Having your athletes available allows the coach to pick from the best players. With that, we also see a pattern of consistency in the starting teams.  Claudio Ranieri was able to repeatedly name the same starting eleven and Leicester City used the fewest number of players across the whole season in the Premier League. 

Similarly, Chelsea made minimal changes to their starting line-up last season, except for the final two games when the title was already wrapped up.

"Having your athletes available allows the coach to pick from the best players"

A Trend Backed by Research?

Professor Jan Ekstrand has been involved in injury in football research since the 1980s, as per the tweet from George Nassis (right)! He and his colleagues at UEFA have continued to collect such information with the Champions League Injury Study.  

In an 11-year follow-up, Hägglund and colleagues found lower injury burden, lower injury incidence and higher match availability to be associated with performance, measured via metrics such as final league ranking, points per league match and success in European tournaments.  The full text is available here on ResearchGate.

"Hägglund and colleagues found lower injury burden, lower injury incidence and higher match availability to be associated with performance"

Athlete Availability in Team Sports Beyond Football

This relationship has also been demonstrated in published research across a range of sports, including the following:

• Raysmith BP, Drew MK. Performance success or failure is influenced by weeks lost to injury and illness in elite Australian track and field athletes: A 5-year prospective study. Journal of Science and Medicine in Sport. 2016 Oct;19(10):778-83.

• Podlog L, Buhler CF, Pollack H, Hopkins PN, Burgess PR. Time trends for injuries and illness, and their relation to performance in the NBA. Journal of Science and Medicine in Sport. 2015 5;18(3):278-82.

• Eirale C, Tol JL, Farooq A, Smiley F, Chalabi H. Low injury rate strongly correlates with team success in Qatari professional football. British Journal of Sports Medicine. 2013 Aug;47(12):807-8.

• Williams S, Trewartha G, Kemp SP, Brooks JH, Fuller CW, Taylor AE, et al. Time loss injuries compromise team success in Elite Rugby Union: a 7-year prospective study. British Journal of Sports Medicine. 2016 Jun;50(11):651-6.

A recent systematic literature review by Drew, Raysmith and Charlton from the Australian Institute of Sport surmises the findings relating to availability and team success, as well as the levels of evidence. The paper was titled: ""Injuries impair the chance of successful performance by sportspeople. I would highly recommend reading this paper.

Injuries not only make athletes unavailable for selection but they may affect the team’s chances of success in more widespread ways, such as enforcing changes to team tactics, disrupting game preparations and causing psychological effects of stress and anxiety both in the injured athlete and potentially in their teammates.

Is Availability of Some Players More Impactful than Others?

Of course, losing certain players to injury may have a bigger impact on the team’s chance of success than others.  Some analyses have attempted to quantify this influence.  For example, the fascinating ManGamesLost.com analysis of the big American team sports uses the Injury Impact to Team (ITT) factor.  This quantifies the impact of an injury by estimating how much time the injured athlete would have played if healthy.  

There are also the financial implications of injuries.  According to sportingintelligence.com and Premier Injuries, the total wage bill for injured players in the Premier League last season was over £131 million.  

Kitman Labs have tried to combine the analysis of the effect of injuries on both team success and the financial implications. They explored this information across the NBA, NFL, MLB, NHL and the MLS.  The analyses found strong correlations between the number of wins and available athlete dollars. For example, in the NBA their analysis found teams with a guaranteed playoff spot had an average of $52 million athlete-dollars available to play throughout the season (see below).  

Final Thoughts

In summary, there appears to be strong evidence of a relationship between success and player availability.  Whether your team’s management is driven by bankroll or on-field success (or both incentives), we are armed with information to support the impact injuries (and therefore avoiding injuries) can potentially have on both performance and finances.

Athlete health and performance are clearly interrelated measures.  However, injuries cannot be prevented altogether and there is a whole spectrum of "prevention".  There is also an ongoing debate regarding how much luck plays a part in injury.  For example, Phil Coles includes luck as a layer in his injury prevention pyramid (BJSM, 2016), which Sheree Bekker questioned in this BJSM post-script.

Evidence of an association between success and injuries can be used to help support the implementation of strategies.  As Drew and colleagues state in their systematic review (2017):

“[W]hen attempting to garner support and adherence to the implementation of interventions (and ongoing participation in injury and illness prevention programmes), one way to improve engagement would be to highlight the link between injuries and impaired performance.”

However, the presence of “Sports Science” or “GPS” or “{insert Sports Technology solution and/or Athlete Data Management System}” alone do not inherently reduce injury risk. It is how this information and expertise are used to decide and implement interventions that may beneficially impact injury risk and therefore, promote availability and ultimately performance and team success.

Frequently Asked Questions (FAQs) on Player Availability

What is player availability?

Player availability refers to how often a player is able to participate for their team, usually in relation to keeping players injury-free. It is often expressed as a percentage and broken down into training and game/competition player availability.

How does player availability relate to team success?

While many factors influence team success, having high availability appears to give your team a better chance of success. Generally having greater availability allows the coach to select from their best players, while also enabling greater consistency in personnel and tactics. Conversley, during times of fixture congestions, greater availability can allow the coach to rest and rotate their players.