The header, the soccer skill of redirecting a ball in flight with one’s head, may be bad for your health. Evidence is mounting that repeated heading in soccer causes subconcussive blows to the head that can lead to traumatic brain injury (TBI), impaired neuropsychological function, and may have been a factor in one death.
A typical headshot
Soccer players take many headshots during games, in practice, and over a career. When heading a high-flighted ball like those kicked by a goalkeeper, the players stiffen the neck muscles and snap the upper body at the in-flight ball to strike it with their forehead.
Successful contact and motion propel the ball away. Concussions from headshots are common but not from striking the ball. Most happen when two players who are dueling to strike the ball hit their heads together.
Concussion: A traumatic head injury
The human brain is protected primarily by the skull and is suspended in a fluid that cushions it. In a concussion, the brain slams against the skull. The forces associated with the impact cannot be absorbed by the cushion.
An athlete who experiences a concussion from a sports-related head trauma may lose consciousness or experience concussion-related symptoms (See below).
SIGNS OF A CONCUSSION
① Headache or pressure in the head
② Nausea or vomiting
④ Sensitivity to light or noise
⑥ Behavior or personality changes
⑦ Numbness or tingling
⑧ Difficulty concentrating
⑨ Difficulty remembering
Headshot: A subconcussive impact
An athlete can receive a subconcussive head injury by heading a ball. The athlete does not experience a visible injury nor are the classic symptoms of a concussion present from the head-to-ball contact.
Biomechanics of the impact from a header: When the ball strikes the forehead, the brain first hits the front of the skull before bouncing back and hitting the back of the skull. Neck strength, technique, and other variables can affect the linear force of the impact.
Scientific evidence is showing that impairment of the brain's function may occur from an accumulation of headers and harmful damage can manifest itself over the long-term.
Death of a frequent header
In April 2012, chronic traumatic encephalopathy (CTE), a degenerative brain disease linked to repeated blows to the head, was found posthumously in 29-year-old former soccer player Patrick Grange of Albuquerque.
An autopsy revealed that Grange had extensive frontal lobe damage in an area of the brain that corresponded to the part of the head he would have used for headers. Grange liked to head the ball and headed it frequently.
Grange was a lifelong soccer player who started playing when he was 3 years old until he was diagnosed with Lou Gehrig's disease at 27.
The frontal lobe is involved with purposeful activities like judgment, creativity, problem solving, and planning. It also holds short-term memory so you can juggle two or more thoughts at once.
Damage to Grange's brain
At 27, Grange was diagnosed with amyotrophic lateral sclerosis, or ALS, a degenerative disease of the nervous system commonly known as Lou Gehrig’s disease. It is usually diagnosed around 55 years of age. The frontal lobe damage to Grange’s brain was believed to be the primary reason for his ALS diagnosis.
Grange's frontal lobe had high levels of the abnormal protein tau, a characteristic that leads to a CTE diagnosis.
A closeup of the normal brain, left, and Grange's brain, right. Dye coloring allow abnormal tau proteins present in the brain to appear as dark brown.
The abnormal deposits of tau in the brains of two athletes compared with a normal brain. The tau lesions are commonly found in portions of an athlete's brain that have experienced repetitive trauma, either from concussion or mild subconcussive hits. The trauma triggers progressive degeneration and death of brain tissue, including the build up of tau. Currently, CTE can be diagnosed only post-mortem.
Breaks in the brain's message network
Using sophisticated imaging equipment, researchers have been able to document impaired neuropsychological functions in elite soccer players who headed the ball frequently but had no histories of concussion. Their symptoms were consistent with those experienced by players who have experienced a mild traumatic brain trauma like a concussion. What they found:
① Glial cells produce an insulating material called myelin that wraps around a neuron's axons, the tails of the neuron cells that transmit messages. Because of myelin, electrical signals can be transmitted along these tails, at high speed, to other parts of the brain.
② Players tested had significantly altered white matter structure. A component of the central nervous system, white matter is the network of glial cells and myelin-coated axons that transmit the brain's electrical messages. Changes, or bad connections, were noticable in regions of the brain that are responsible for memory and attention.
Evidence stacks up on heading frequency
Some key points from other recent studies on soccer players who head the ball regularly and have brain abnormalities similar to those found in patients with concussion (mild traumatic brain injury).
Hits with the head
Number of times an athlete headed the ball headed during a game
Velocity of the ball in a game
Number of times an athlete headed the ball during practice
Serious players: 37 adult men and women who had played soccer since childhood were tested ...
» Those who headed more than 1,100 times in the previous 12 months had significant loss of white matter in parts of the brain associated with memory, attention, and processing visual information compared with players who headed the ball less often.
» Those same players were substantially worse at recalling lists of words read to them, and forgot or fumbled words far more often, reflecting a pattern of behavior typical of someone who had a serious concussion.
College players: The heading history and cognitive health of 51 male and female players was tested during the season ...
» Players who headed the ball more often during the season, including practice and games, performed worse on a visual memory test that measured the ability to recall shapes and images, and they had more headaches and episodes of dizziness.