The hamstrings are a group of muscles composed of the semitendinosus, semimembranosus, and biceps femoris on the back side of the thigh. These 3 muscle tissues connect the sciatic tuberosity to the tibia and fibula, all covering the knee. Because of the nature of the sport, sprains, strains and tears of the hamstrings are frequent in soccer players. Surveys done by UEFA in the Champions League show that muscle injuries account for more than 30% of all injuries. Of these, nearly 90% of muscle injuries occur in the four main muscle groups of the lower limb: hamstrings, adductors, quadriceps and gastrocnemius.
Of these, hamstring injuries are the most common muscle injuries, accounting for more than 33% of all muscle injuries and up to 12% of all sports injuries. Moreover, 70% of hamstring injuries are acute episodes, and 96% even occur in non-contact situations, which can be defensible. The number of hamstring injuries is 3.7 per 1,000 hours when measured in hours of training and competition. This means that a 25-man professional men's soccer team will suffer at least five hamstring injuries per season, with a recovery time of over 80 days and the injured player missing at least 14 games. The incidence of hamstring injuries has not declined in recent years, despite the large number of high-tech wearable devices that collect big data for "preventive" muscle fatigue assessment.
Hamstring injuries not only affect team performance, they also affect clubs financially. If a popliteus injury occurs to a superstar such as Lionel Messi, C-Ro, or Kylian Mbappe, and it occurs during a crucial period in the Champions League or a league match, the impact is sure to radiate into the economic and even social spheres. Aside from soccer, hamstring injuries in rugby are the injury that causes players to miss the most games. The average Australian Rugby League club misses up to 20 matches per season due to hamstring injuries, with frequent sprinting being cited as the main reason for hamstring injuries. The only silver lining is that the recurrence rate of hamstring injuries has steadily declined over the last 20 years, from 40% to 13.5%, largely due to high tech rehabilitation techniques and more conservative injury healing strategies by the team medical team.
It's important to note that hamstring injuries are more likely to occur during preseason training and preseason games, when the probability of pulling a muscle is greatly increased because players are coming off of summer vacations, are not yet back to their optimal condition, and are rushing to get back into game shape through intense training. Muscle injuries typically account for 46% of training injuries and 22% of preseason injuries. More than half of hamstring injuries occur before the start of the season, when the team hasn't even played 1 league game. The 1 month before the start of the league season is also a high prevalence period for hamstring injuries, which can be triggered by external factors such as high summer temperatures, in addition to intense training.
Hamstring injuries in soccer often require more time for rehabilitation than in other sports. This is related to the fact that soccer involves more movements combining hip flexion and full knee extension.
Messi's underperformance in Paris last season, in addition to the after-effects of contracting the new coronavirus, was directly related to the hamstring injury he sustained in his left leg last November. Back before the 2006 World Cup, the youthful Messi had missed up to 70 days with a hamstring injury. Although Pekelman trusts the injured Messi, but it is also the injury problem that makes the Argentine manager dare not let go of the use of Messi, resulting in the team was eliminated by Germany.
135 million euros to join Barcelona's Dembele, is the "popliteal curse" of one of the biggest victims. After joining Barcelona, he has had as many as nine popliteal injuries, including six popliteal injuries in the left leg and three popliteal injuries in the right leg. Dembele missed as many as 22 games in 2017/18 alone and 24 in 2019/20. The British insurer had conducted a survey to assess Premier League player injuries in the 2018/19 season prior to the outbreak of the new Championship epidemic, which showed that was the season with the highest number of injuries and costs incurred since the data was first released in 2012. A whopping 764 injuries were recorded, a 15% surge on the previous season and a reversal of the previous 10% annual decline. The report, which also calculates the financial cost of player injuries, mainly the salaries clubs have to pay while players are injured, has risen from ￡119m in 2011/12 to ￡221m in 2018/19.
The majority of these injuries and losses come from muscle injuries, particularly hamstrings. Compared to other injuries, hamstrings are difficult to assess injury risk through big data analytics and have a relatively higher rate of recurrence. In soccer, hamstring injuries have a recurrence rate of 16% and most occur in the biceps femoris. Recurrence rates for hamstring injuries in other sports were somewhat higher, up to 33% in Australian rugby and 21% in English rugby. Furthermore, old hamstring injuries can take longer to heal than the first time they occur, and only a few giants, with their expensive, high-tech rehabilitation facilities, are able to allow players to recover from old hamstring injuries for a similar period of time as the first time they occurred.
Of course, the likelihood of hamstring injuries and the rehabilitation period varies depending on the intensity of the match. For example, the incidence of hamstring injuries in the Qatar League is about 20% lower than in the Champions League, both in training and in matches, and the recurrence rate is about 33% lower. As for the average amateur, the probability of occurrence is even lower. Nonetheless, all soccer fans should take hamstring injuries very seriously, as they are the "king of muscle injuries".