Messi vs. Mbappe, who will win? No matter who it is, they will face this kind of injury!

The 2022 Qatar World Cup will usher in the final battle at 23:00 Beijing time tonight. Powerful shots, volleys, headers... Every powerful shooting duel in the World Cup makes people excited. At this time, if the goalkeeper blocks the ball with his body, it will inevitably make our palms sweat.

The loud "bang" sound can be clearly heard in the broadcast. How painful would it be if the ball hit someone?

01

How fast can a football fly?

To answer this question, first of all, we need to know how fast a football can fly.

In a 2011 Castrol-sponsored ad documentary, Portuguese soccer star Cristiano Ronaldo used the outside of his foot to kick the ball at high speed through triple-layered glass.

The most powerful shot in football is the one with the outside of the foot. The entire instep is used to transmit the power of the leg swing and the accelerated running to hit the football. A high-speed camera recorded the speed of the ball at that time. At the moment the ball flew out, the speed reached 128.7km/h, which is faster than the car on the highway .

Ronaldo is not a player known for his powerful volleys. In some unofficial records, many people have kicked shots faster than this speed. In a Brazilian minor league match, an unknown player named Ronny Heberson kicked a free kick at a speed of more than 200 km/h. In the low-definition video, the camera did not catch up with the moment the ball was kicked, and the goalkeeper did not react at all.

02

How much would it hurt to get hit?

So, how painful is it to be hit by such a ball? If a car is running at this speed and hits any object, it will definitely be a car-destroying accident. This is because the momentum of an object is proportional to both speed and mass. For a high-speed object to have great destructive power, it must have both speed and mass .

Fortunately, the mass of a soccer ball is not large, about 400 grams, only one-fifth of a car; and the speed will also decrease due to air resistance when flying. For example, the goalkeeper's "long kick" over half the field will have a relatively slow speed when it falls. In order to pursue the angle and arc of the free kick or corner kick in the air, the player usually kicks out a trajectory with a certain amount of rotation, which will further reduce the speed of the ball.

The speed of an average player's shot is generally around 40-60km/h. No wonder defenders and goalkeepers just grimace after being hit.

Moreover, the football itself is made of relatively soft leather or synthetic materials, and is inflatable, and the elastic material will greatly reduce the impact force. The only thing that needs to be repeatedly impacted by the football is the goalkeeper's hands. Fortunately, the gloves they wear will also greatly reduce the impact force of the ball.

The only thing you need to worry about is that when you are lining up for a free kick, you need to protect your "vital parts" with your hands or turn your face away. If you are hit by a strong shot, it usually only hurts for a while, and serious injuries are rare.

03

Heading is the real danger

However, there is one part of the human body that we often overlook - the head. About one in five injuries in football come from concussions caused by head impacts. Severe concussions can cause coma or even life-threatening situations (for example, former Chelsea and Czech goalkeeper Petr Cech suffered a concussion and skull fracture due to an impact, and has been wearing a helmet ever since); most concussions are mild to moderate, manifested by dizziness, nausea, loss of balance, etc., and can be recovered quickly. But the vast majority of these concussions come from collisions between the head and hard objects, such as another player or a goalpost. Concussions caused by powerful shots are rare.

But active and conscious collisions also happen frequently, such as the wonderful headers in football matches. Headers are truly dangerous .

Compared to other parts of the body, the head lacks the protection of muscles or fat tissue . Anyone who has practiced football knows that heading is difficult and requires repeated practice. One of the tasks of practice is to get used to the impact of heading and use various techniques to transfer the angle of the ball over the head and keep the impact force while flying towards a specific target. Studies have shown that such repeated, moderate-intensity impacts are likely to cause chronic damage to the head.

There is no obvious impact on the player's consciousness and feelings at the time of the impact, and the changes brought about by this long-term and continuous impact can only be discovered through brain imaging scans or comprehensive cognitive measurements.

Researchers at the University of Chicago School of Medicine[1] call this "subconcussion." The damage caused by subconcussion was first discovered in American football players. A considerable number of retired players have developed cognitive impairment early; even some athletes who have never had a history of concussion have developed brain lesions. Imaging scans have found that the pathology of these degenerative lesions is consistent with the damage caused by chronic traumatic impact on the brain, but it is more hidden and difficult to detect. A study of retired athletes[2] showed that compared with track and field athletes, the cerebral cortex of retired football players is more likely to become thinner with age, which may accelerate cognitive decline.

According to statistics[3], during each football match, each player will make 6-12 headers on average. Including training, each player needs to make hundreds or even thousands of headers each year, which is definitely not a small number. However, the specific injury mechanism needs to be revealed by more research, and the existing number of studies and samples is far from enough. Moreover, the situation of head injury will also vary greatly due to different positions on the field and other factors of the individual's body.

Therefore, there is no definitive conclusion that "heading is harmful to health". However, some European youth training clubs have tried to reduce the intensity of heading training for teenagers. After all, children's heads are not fully developed yet, which is also a safer consideration.

Summarize:

To sum up, being hit once or twice by the ball is not a big problem, but being hit on the head repeatedly and continuously by the ball is still a hidden danger . Sports have risks, so everyone should pay more attention!

So, will it be the Argentina team led by Messi, or the French team with a group of attacking players such as Mbappe, who will lift the World Cup trophy for the third time tonight?

References:

[1] Bailes JE, Petraglia AL, Omalu BI, Nauman E, Talavage T. Role of subconcussion in repetitive mild traumatic brain injury. J Neurosurg. 2013 Nov;119(5):1235-45. doi: 10.3171/2013.7.JNS121822. Epub 2013 Aug 23. PMID: 23971952.

[2] Koerte IK, Mayinger M, Muehlmann M, Kaufmann D, Lin AP, Steffinger D, Fisch B, Rauchmann BS, Immler S, Karch S, Heinen FR, Ertl-Wagner B, Reiser M, Stern RA, Zafonte R, Shenton ME. Cortical thinning in former professional soccer players. Brain Imaging Behav. 2016 Sep;10(3):792-8. doi: 10.1007/s11682-015-9442-0. PMID: 26286826.

[3] Rodrigues AC, Lasmar RP, Caramelli P. Effects of Soccer Heading on Brain Structure and Function. Front Neurol. 2016 Mar 21;7:38. doi: 10.3389/fneur.2016.00038. PMID: 27047444; PMCID: PMC4800441.

Author: Li Zi

Review | Lu Wei, Associate Professor, School of Sports Medicine and Rehabilitation, Beijing Sport University