Biomechanics in Football


Biomechanics is the study of the movement and the forces that are generated within a body. The field of biomechanics also focuses on such forces and movement of the mechanical structure of the body to the tissues, fluids, and other body sections used in identifying ailments and treatment (Rogers, 2019). Biomechanics analyzes human body movement patterns in various human activities. Various biomechanical models represent the physics of the movement of the human body. They help people obtain tips from the full-body, full-body movement data, and help in projecting the possibility or ability of the body to achieve a certain objective.

Figure 1: Biomechanics

Source: (Rogers, 2019)

In football, various models have been used to give insights to players on how best they can utilize their abilities and perform better. Such models help the players and football analysts understand how best the body can perform in football, minimizing severity. This case study will focus on the model of the hip and knee joints in football. It will explain the application of this model and recommend how to apply it to players in their football careers.

The Model of the Hip and Knee Joints

The model of the hip and knee joints is extensively used in football. Players in this sport must perform intensive and repetitive tasks with their bodies, including sudden increase and decrease in speed, direction changes, and jumping (Cleather, Goodwin, & Bull, 2013). This high demand for intensive tasks may lead to burning out and overloading the joints, which can lead to impairments during a game and end in causing significant accidents. It is important, therefore, to analyze adaptations in football for the lower extremity joints to give insights on preventing and initiating exercises to recover (Lopez-Valenciano, Ayala, Vera-Garcia, & Croix, 2017). Studies have shown a normal impact of football on the knee and the hip joints (Wilcox, Osgood, White, & Vince, 2015). This made many football healthcare professionals pay little attention to the hip and knee joints during the testing at the beginning of a football season. They also overlook questioning the exercises done during the training. Some kind of stretching during training and exercises can be used as a preventive measure to lower the risks and injuries that may occur during the match (Davis, 2018).

Few types of research have been done on football-specific adaptations on the hip joint and the ankle may be among the top primary risks in common football injuries (Rey, Penas, Casais, & Ballesteros, 2012). These injuries may be ankle sprains and knee osteoarthritis (Petrillo, Papalia, Maffulli, Volpi, & Denaro, 2018).

In a study to analyze the impact of football on the knee and the hip joints (that led to the formation of this model), computation of the muscles and ligament forces for a normal person’s manner of walking. The electromyography data of muscle forces in a state of inactivity and the bone ligament forces that become tight during a specific gait period were also eliminated. The data from the experiment was used alongside some photographic establishments of the knee, ankle, hip, and foot. This provided the researchers with data on joint rotation and movement. In determining the force of the net reaction at the knee, 6 motion equations were used. The problem could not be determined while identifying the components of bone contact force and the force of muscles and ligaments (Woodling, 2013). The study was repeated several to ascertain the results.

Another method to develop the model on the hip and the knee and reduce the inability for the impacts to be determined was to compare the forces of the ligaments around the knee joint with the angle at which the knee flexed.  Three-dimensional knee joint kinematics was considered to evaluate the surface area, establishing the contact condition of the middle and the surfaces on the sides. Several calculations were done to measure the joint locations against movements, rotation, and the moment the joints are constrained.

 Several other studies were in coming up with is model. The hip joint models and the knee joint models have arrived in the same way. It was assumed that the hip joint transmitted a force of contact that a maximum of two muscles were active at any given gait. All the studies identified that the knee and hip kinematics are similar across all positions.

The model of the hip and knee has therefore undergone multiple tests to identify high-performance postures, styles, and techniques and possible impacts of physical contact and load. The knowledge about this mode equips one with how to exercise or carry out the non-surgical or non-operational recovery of the knee or the hip for athletes who have adverse effects from playing.

Players who understand the hip and knee model are better placed for quick recovery after matches. However, coaches and trainers also need to understand this model as it helps them give the most relevant training to the players to reduce the chances of injuries and maximize their performance during matches. Sports medical professionals need to appreciate this model while conducting various therapies to the athletes and also suggest such best practices to the teams in ensuring each player performs at their optimal level of comfort and ability based on biomechanical models.

Application of the Model of Hip and Knee Joints

Knowledge of the hip and knee joint model has been very useful to young American footballers. This has been led by the youth’s prevalence of hip and knee replacements. Joint displacement exposure has a direct relationship with the possibility of osteoarthritis. However, there is a mitigation opportunity for this condition when the risk factors are identified. The number of young people in football in America makes it an important consideration to identify the risk factors of osteoarthritis, supporting the future prevention of the same.

A study was done on the American National Football League (NFL) retired players. 11.4% of players who participated in the survey reported joint replacements after retiring from football. Among these athletes, 7.7% reported knee replacement more than hip one (Davies et al., 2019). More than half of them disclosed that they previously had a severe injury to the knee. Therefore, this shows that knee replacement is more prevalent in the National Football League in America than hip replacement.

Osteoarthritis is among the most disturbing chronic diseases across the world. Although it is often associated with the elderly members of society, young professional football players are also at risk of getting the disease. Among the young athletic population, the major causes of this disease are injuries during their occupation and obesity (Amoako & Pujalte, 2014). There have been an alarming increase in articulate cruciate ligament (ACL) injuries among young female in sports. Female players have been more prevalent to such injuries than their male counterparts (Ratzlaff & Liang, 2010).

This research finding has led to the initiation of the joint replacement program in the national football league (NFL). The young professional players in the league have been undergoing stretches exercises and therapeutic programs to prevent them from suffering from hip and knee replacement upon retirement, are found with most of the already retired athletes.

The athletes learn the workout practices that can help them overcome the possibility of injuries and Osteoarthritis in the future of their football career. This is a result of a study that showed that hip and knee joint-related diseases were more prevalent in retired athletes than in the general population (Golightly & Callahan, 2009). Those with such conditions in the general population mainly included people above 60 years, confirming that for the general population, the disease is caused by old age. However, it is closely related to their career for the athletes, who predominantly have such a condition.

The prevention measures that players in the National Football League started to take in the programs have proven to benefit them and help them avoid such joint problems. As seen earlier in this study, the main risk factors among athletes are injuries. Therefore, players in the national football league (NFL) are usually advised to avoid any cause of injuries during matches to reduce their chances of getting hip and knee model-related diseases. Other measures have been used to mitigate knee injuries. A study on the national football league showed a close relationship between cold weather and outdoor stadiums with natural grass or man-made carpet and reduced knee, ankle, and hip injuries (Ratzlaff & Liang, 2010). Further, a biomechanical study revealed that high shoe surface friction interferes with the natural biomechanical movement of the body and joints and hence leads to injuries (Dowling, Corazza, Chaudhari, & Andriacchi, 2010). Therefore, from such studies, the teams in the national football league in America have taken initiatives in their programs to focus more on outdoor stadiums and have their matches during the cold weather. Secondly, during their training, the teams have also emphasized no—friction football shoes to help lower the chances of hip, knee, and ankle injuries.

Suggestions to the Observed Participant

Football athletes should, therefore, observe the following measures to avoid injuries to improve their performance;

  • The participant should avoid sports shoes that increase friction. This is because the friction alters the natural biomechanical model of the hip and knee joints, forcing them to change their movement and exposing her to injuries. Therefore, sports shoes that do not have much friction will ensure that she improves her performance.
  • The observed participant should also ensure that she does her exercises during cold weather and in open fields. She should also suggest the whole team do more outdoor matches than indoor matches and also do their matches in cold weather. This is to reduce the possibility of injuries as it has been seen that studies have linked outdoor stadia and cold weather to reduced injuries of the hip and knee joints (Ratzlaff & Liang, 2010).
  • The participant should stretch at the given angles to accurately target the hip and muscles(Fischer, 2013). This will ensure that she becomes more flexible and comfortable kicking the ball, improving her overall performance.


Therefore, the model of the hip and knee joints is a key factor for football teams to consider in ensuring improved performance. The measures suggested (Petrillo, Papalia, Maffulli, Volpi, & Denaro, 2018)keeping healthy hip and knee joints also help athletes to avoid the possibility of Osteoarthritis after retiring from football. By considering this model during exercises and matches, football sports performance will be improved, and there will be reduced injuries happening to athletes, consequently reducing cases of osteoarthritis among retired soccer players.


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