Doubling of the proportion of hamstring injuries and rest days for male professional footballers in the last 20 years
Almost a fifth are recurrences; more than two-thirds of these occur within 2 months of returning to play
The proportion of hamstring injuries and associated days out of matches among European professional footballers has doubled over the past 20 years, according to a study published online in the British Journal of Sports Medicine .
The hamstring muscle group is made up of three muscles in the posterior thigh region:
These are mainly leg flexors and extensors secondary form of the thigh. When walking or running, they are also antagonists of the quadriceps, slowing the advancement of the leg at the end of the leg and preventing full extension of the knee. |
Nearly one in five of these injuries were recurrences, more than two-thirds of which occurred within 2 months of returning to play, the findings show.
An injury occurs when tendons (strong bands of tissue) or large muscles in the back of the thigh become strained or torn.
The number of hamstring injuries in men’s professional football sustained during matches remained stable between 2001 and 2014, after which it increased, prompting several initiatives to reduce the risk. But it is not known whether men’s professional soccer clubs have flattened the hamstring injury curve since 2014.
To try to find out, the researchers set out to explore trends in the number and types of hamstring injuries over the past 2 decades (2001/02 to 2021/22), with a particular focus on the 8 most recent seasons (2014/2021). 15 to 2021/22).
They included 3,909 players from 54 teams in 20 European countries that competed in 21 consecutive seasons.
All players were part of the Elite Club Injury Study (ECIS), which the Union of European Football Associations (UEFA) started in 1999, with the aim of reducing injuries in football and increasing player safety.
The researchers analyzed data collected by medical teams on the amount of time players spent in training and matches; periods of absence due to injury, illness or other reasons; and type of injury (structural or functional).
Injury severity was classified according to the number of days out between injury onset and return to play: mild (none); minimum (1–3); mild (4–7); moderate (8-28); and severe (more than 28 days).
Over 21 seasons, 2,636 hamstring injuries were reported during a total of 2,131,561 hours of training and matches: 922 (34%) during 1,787,823 hours of training and 1,714 (66%) during 343,738 hours of matches.
The proportion of these injuries doubled between the first and last seasons, going from 12% of the total injuries in the first, to 24% in the last, and comprising almost a fifth (19%) of the 14,057 injuries recorded during the study period.
Similarly, the days of absence due to hamstring injuries doubled, going from 10% to 20% between the first and last seasons, and constituting 14% of the total days of absence during the study period.
The risk of a hamstring injury was 10 times higher during matches than during training, while the average rest period was 13 days.
Overall, 1 in 5 players missed training or games due to a hamstring injury in a given season, and a team of 25 players can expect around 8 hamstring injuries each season. , say the researchers.
Of all hamstring injuries, nearly one-fifth (475; 18%) were recurrences, and early recurrences (325), within 2 months of return to play, made up more than two-thirds (69%) of these . All recurrences were 9 times more likely to occur in matches than in training.
Between 2014/15 and 2021/22, time trend analysis revealed a significant increase in the number and severity of hamstring injuries during training.
Over the entire study period, the majority (71%) of hamstring injuries were structural and were associated with more days of rest than functional injuries, averaging 17 vs. 6.
Development of hamstring injury incidence and injury burden during the study period. Injury incidence is defined as the number of injuries per 1000 hours of exposure, presented with a 95% CI. Injury burden is defined as the number of days of absence caused by 1000 hours of exposure and is presented as the average of participating teams with DS. The shaded area represents the most recent eight-season period that has not been previously published.
This is an observational study, and the researchers freely acknowledge that they did not set out to explore the reasons for their findings. But, based on 21 years of observations, they suggest this could be a combination of more intense matches and a crowded fixture schedule.
“The intensity of elite men’s football has increased over at least a period of the years included in this study. Current soccer practice includes a large volume of high-intensity soccer actions. “Professional players now perform more high-intensity activities per game than before and also run faster than their predecessors,” they explain.
“Professional players now work all year round, apart from a 4-6 week break between seasons. Even during the traditional break between seasons, players are often required to go on preseason tours that require intercontinental travel.”
Conclusions
The proportions of hamstring injuries, in number of injuries and days of total absence, doubled during the 21-year study period. Over the past eight seasons, hamstring injury rates have increased in both training and games.
What is known
What does this study contribute?
How it can affect practice These data on the incidence and burden of hamstring injuries provide a strong rationale for teams to continue to focus on preventing initial and recurrent hamstring injuries. The high rate of recurrent hamstring injuries within 2 months of return to play suggests that this period is a particularly important time for team physicians to: (1) carefully monitor players who complete evidence-based rehabilitation; (2) manage training and match loads; and (3) maintain preventive programs. |
