Why Are We Seeing So Many Hamstring Injuries in Elite Men’s Soccer?
As the Premier League enters its winter break, the two week shutdown will come as a welcome respite for a number of clubs. Match-day 20, which marks the beginning of the second half of the season, saw more than thirty players unavailable for one specific reason – hamstring injury. This seems to be an incredible statistic, but is one which shouldn’t come as a complete surprise. Data recently published from the UEFA Elite Club Injury Study has revealed that hamstring injuries in men’s professional soccer have doubled in 21 years, from 12% of all injuries in 2001/02 to 24% in 2021/22. So, what is driving this upsurge?
Fixture Congestion & Load Management
The packed Premier League schedule has long been a source of complaint for managers and coaches, who cite concerns about the impact that the heavy workload has on player welfare – fears highlighted by the end of year program requiring some teams to play three times in six days. The physical demands accompanying soccer match-play create inflammation and structural damage in the muscles – and depending on the intensity of the game, this can take players over 72 hours to recover from (3). A rapid turnaround of games means that players are unlikely to have enough time for full recovery to take place, a problem which is exacerbated by travelling to and from games.
Incomplete recovery and an accumulation of fatigue – both physical and mental – can result in underperformance and injury, a fact which is underlined by the UEFA Elite Club Injury Study reporting that excessive player load and overuse were responsible for a reported 12% of hamstring injuries (4).
The Intensity of Soccer Has Increased
A study published in 2014 which looked at the physical outputs produced by Premier League players over a seven-year period revealed that, while the total distance players were covering increased by only 2%, their high intensity running increased by 30% and their total sprint distance increased by 35% (2). When this was broken down further, the researchers found that the number of sprints players were performing had actually increased by 85% (2). A more recent paper published in 2023 found significant increases both in high intensity running and in sprint distance over a five-year period, confirming that the high intensity component of Premier League soccer has continued to increase (1). Sprinting is by far the most common mechanism of hamstring injury in soccer (6), with the UEFA Elite Club Injury Study reporting 61% of injuries occurring through sprint mechanisms (4). With players performing more high intensity activities and running faster than before, an increased number of sprints results in greater risk to the hamstring, and consequently, in more injuries.
Games Are Lasting Longer
In the 2023/24 season the Premier League introduced a new initiative to reduce time-wasting and ensure that time added on for stoppages was calculated more accurately. A result of this directive is that games are lasting longer, which could be a contributory factor to the increased number of hamstring strains we are witnessing. The UEFA Elite Club Injury Study established that almost 50% of hamstring injuries occur during the last 15 minutes of the first and second half, when players are fatigued (4). So far this season, the average amount of added time in Premier League games has increased by over 3 minutes compared to the previous campaign (equivalent to 27%), meaning there is a much larger window in which hamstring injuries are likely to occur.
Changes to Coaching Staff
The 2022/23 season witnessing a record 14 changes in the head coach position, with the average tenure of a Premier League manager currently calculated as being less than two years – and this has the potential to have a profound impact on a team’s injury situation. Players become adapted to a particular way of training, and unexpected changes to their normal, established routine can increase the risk of injury. Studies in elite soccer have shown that changing coaching staff mid-season – specifically where a new head coach brings with them their own performance/fitness staff – can lead to a 3-fold increase in hamstring injury (5), with the sudden adjustment to a new playing and training philosophy accompanied by a rise in the number of injured players.
Imagine a club appointing a new coach midway through the season who implements a radically different tactical model focusing on rapid counterattacks – unless this transition is carefully monitored, the sudden change in physical load, particularly a spike in high speed running, could expose players to a greater risk of hamstring injuries.
Conversely, reducing training load can also lead to an increased risk of injury in games, due to players not being adequately prepared to cope with the greater physical demands experienced during match-play. Both over-training and under-training can increase hamstring injury risk, therefore achieving a balanced and optimal training load during staffing changes is a crucial factor for injury reduction.
High Rate of Re-Injury
The UEFA Elite Club Injury Study found that of all the hamstring injuries they surveyed, 18% were recurrences, with early recurrences (within two months of the index injury) making up 69% of these (4). Re-injury is a factor which may well be contributing to the current hamstring epidemic, calling into question the rehabilitation and return to play protocols currently being used. When we take into account the fact that re-injuries cause significantly longer absences than the original injury, these figures suggest that the pathway taken to successfully return an injured player to full and unhindered performance may need to be re-addressed.
- Hamstring injuries in elite men’s soccer have doubled in 21 years, from 12% of all injuries in 2001/02 to 24% in 2021/22.
- The high intensity and sprint component of soccer has significantly increased during this period – Sprinting is by far the most common injury mechanism in soccer, and is responsible for a reported 61% of all hamstring strains.
- Congested fixture schedules and increased travel frequency limit opportunities for recovery and regeneration to take place – 12% of hamstring injuries are due to excessive load and overuse.
- Increased added time in games has created a larger window when hamstring injuries are most likely to occur – Almost 50% of hamstring injuries occur during the last 15 minutes of the first and second half.
- High performance expectations have increased the turnover rate of coaching staff, with changes to playing and training philosophy increasing the risk of injury – The combination of a new head coach and performance/fitness staff can increase hamstring injury risk x3.
- Rehabilitation and RTP protocols potentially need to be re-addressed – 18% of hamstring injuries are re-injuries, with early recurrences (within two months of the index injury) making up 69% of these.
As The Demands Of Soccer Evolve – So Must Injury Reduction Strategies
Soccer is constantly evolving. Competitive matches at the elite men’s level are getting faster, lasting longer and being played more often. These and other factors may well be contributing to an increase in hamstring injuries – but the game is unlikely to revert back to the way it used to be. If teams are going to ensure that their players stay healthy, injury free and available for selection as much as possible, they may have to adapt the way they operate in a changing environment. But how can they achieve this?
One thing that is becoming increasingly clear is that effective communication within soccer teams is a vital – and often overlooked – component of reducing injuries. One of the most significant recommendations from the authors of the UEFA Elite Club Injury Study was that ‘clubs with good internal communication showed fewer injuries and greater player availability’. All information and data which is relevant to injury prevention has to move efficiently between the different departments within a club, and this level of communication has to be maintained when there are staffing changes. New staff can bring with them new ways of communicating, hampering the flow of information and increasing the risk of injury. This highlights the importance of soccer teams operating with a consistent communication and information sharing platform – one which is designed to facilitate collaboration between all departments, and which is robust enough to maintain high quality communication when there are changes in staff members.
About ApolloV2 Athlete Performance Software
ApolloV2’s athlete performance software unlocks data silos allowing GMs, coaches, trainers, doctors and players to become masters of data-driven performance and injury recovery with real-time data visualization and collaboration tools. Our software is integrated with over 50 performance focused technologies used by college and professional athletes. With ApolloV2, teams have the information they need to minimize injuries, optimize player availability and win.
Written by Adrian Lamb, ApolloV2 Sports Scientist
2) Barnes C, Archer DT, Hogg B, Bush M, Bradley PS (2014) ‘The Evolution of Physical and Technical Performance Parameters in the English Premier League’, International Journal of Sports Medicine, vol.35 (13), pp 1095-100
3) Doeven SH, Brink MS, Kosse SJ, Lemmink KAPM (2018) ‘Postmatch Recovery of Physical Performance and Biochemical Markers in Team Ball Sports: A Systematic Review’ British Medical Journal Open Sport & Exercise Medicine, vol.4 (1)
4) Ekstrand J, Bengtsson H, Waldén M, Davison M, Khan KM, Hägglund M (2022) ‘Hamstring Injury Rates Have Increased During Recent Seasons and Now Constitute 24% of All injuries in Men’s Professional Football: the UEFA Elite Club Injury Study from 2001/02 to 2021/22’ British Journal of Sports Medicine, vol.57 (5)
5) Ekstrand J, Van Zoest W, Gauffin H (2023) ‘Changes in Head Staff Members in Male Elite-Level Football Teams are Associated with Increased Hamstring Injury Burden for That season: the UEFA Elite Club Injury Study’ British Medical Journal Open Sport & Exercise Medicine vol.9 (4)
6) Jokela A, Valle X, Kosola J, Rodas G, Til PL, Burova M, Pleshkov P, Andersson H, Pasta G, Manetti P, Lupón G, Pruna R, García-Romero-Pérez, A, Lempainen, L (2022) ‘Mechanisms of Hamstring Injury in Professional Soccer Players: Video Analysis and Magnetic Resonance Imaging Findings’ Clinical Journal of Sport Medicine: Official Journal of the Canadian Academy of Sport Medicine