15 June 2021

The campaign for football glory in EURO 2020 has started. “Keeping your players healthy increases your chances of success”, says Martin Hägglund, who works with elite football players and their injuries.

soccer game.Researchers at LiU study factors that affect the risk if injury in soccer. Photo credit matimix Over 20 years ago, the Union of European Football Associations (UEFA) was concerned about the match programme for elite players and the number of matches they played in a season. How was it affecting the risk of injury? This was the start of research into injuries in elite football conducted by the Football Research Group (FRG), an international research group with its academic home at Linköping University under the leadership of Professor Jan Ekstrand.Martin Hägglund.Martin Hägglund. Photo credit Emma Busk Winquist

“We started the first injury study in 2001, with a dozen clubs selected by UEFA. Today, we have extended the work, and all 32 clubs that participate in the Champions League, the main tournament for clubs in Europe, are invited to join. This is the most extensive study that has been conducted within football, and one of the largest of its type within elite sport anywhere in the world”, says Martin Hägglund, professor of physiotherapy at the Department of Health, Medicine and Caring Sciences, LiU.

He became involved in planning the Uefa Elite Club Injury Study (ECIS) while studying to become a physiotherapist, and continued to take a doctoral degree in the field. He is himself an ex-football player, and took his interest for sport from the field into the research lab.

“As expected, we saw that players who played a lot of matches suffered more injuries, and performed more poorly in the following European and World Championships. The results from our study were an important factor in the decision to reduce the number of matches in the Champions League, to give the players slightly longer rest periods.”

The research has shown that a congested match calendar increases the risk of injury. The main effect is that muscle injuries, i.e. muscle strains and pulls, become more frequent. One measure to reduce the risk of injury is for the team management to rotate players in the squad, such that each player plays fewer matches. The researchers have also seen that the teams that can reduce the number of injuries are more successful in the leagues, and progress further in European cup tournaments.

High risks during the European Championship

The researchers are also conducting studies of injuries during the European Championship this year, following national teams in the same way as they follow club teams.

“We see that the risk of injury tends to be slightly higher during European tournaments than in club football. We believe that this is linked to the congested playing schedule. All matches are extremely important, and we have seen that the intensity of play increases for such matches, with more player-player contact. Another explanation could be a higher risk acceptance among the teams, allowing players with niggles to play in matches during important phases of the tournament. Even so, of course, it’s still the case that teams that can keep players on the pitch have greater chances of success, also in the European Championship”, says Martin Hägglund.

Researchers at LiU act as a central hub for the ECIS study. They collect information from the medical personnel working with the various teams. They look at the number of training sessions and matches that the teams play, and the football-associated injuries and illnesses in the squads. This information is analysed to obtain a better idea of, among other things, the types of injury that occur most often, whether the types of injury vary through the season, whether older and younger players are affected differently, and whether playing position affects the type of injury. Knowledge about the risk of injury can inform measures to prevent injuries in elite football players.

Injuries and their impact on future health

Martin Hägglund is driven by an ambition to reduce the negative effects on the health of the athletes.

“Elite sport is in the borderland between what is healthy and approaching unhealthy, with overload and injuries. It’s not just about problems that the injuries cause here and now: it also concerns health problems that can arise later in life. We know that those who have been affected by, for example, a severe knee injury during their sporting career run a significantly higher risk of developing early arthritis in the joint. This means that elite athletes can experience problems later in life caused by their sporting career, and it is therefore important to ensure that players stay injury-free.”

An important part of the study are the statistics and summaries that the researchers send back to the clubs. A club can in this way benchmark their performance against other clubs and get an idea about what it appears to be doing right when it comes to certain types of injury. The medical personnel in the different teams also share information such that they can learn from each other and work together in reducing the risk of injury.
Many of the insights that are gained from studying injuries within elite football can also be used in amateur and youth football. During his PhD studies, Martin Hägglund looked at good examples from elite football and used them to create a step-by-step process for players returning to play after an injury.

“The study we conducted showed that it was possible to reduce the rate of re-injury significantly by following the criteria that we adapted from the elite clubs. It comprised concrete advice and a checklist to gradually increase the load when returning to play after an injury.”

Concussion – how dangerous is it?

Twenty years of research into football-related injuries have given many insights, but we still need more research and new knowledge. In recent years, more research has been carried out concerning problems of head injury and concussion among football players and other athletes.

“I believe it would be interesting and important to be able to study in more detail the sorts of injury that can give consequences later in life, and what happens for elite athletes after their sports career. Can we improve the way in which we detect and record concussion, take the affected players out of the game for assessment and rehabilitation, and introduce the protocols that have been established by various international working groups within sports medicine?”, asks Martin Hägglund.

The Covid pandemic that has dominated everyday life around the world has affected sporting activities, and several major football leagues have been cancelled. The researchers are now studying the consequences of the Covid pandemic for elite football with respect to injuries, and periods that players have been off sick, infected by the Covid-19 virus.

But first, we have to get through EURO 2020. Are you planning on watching the matches?

“Of course!”

Translation by George Farrants.

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