That’s the encouraging conclusion of a major US study comparing ‘neurocognitive’ function in three groups of students at the University of North Carolina, comprising:

• 91 male and female foootballers, with an average of 15 seasons of prior participation in the sport;
• 96 athletes, other than footballers including players of women’s field hockey, women’s lacrosse and men’s baseball;
• 53 non-athlete ‘controls’.

The football players were further divided into two groups: those with and without a history of concussion.

The researchers were testing the theory that extended exposure to football may be associated with chronic impairment of brain function, as put forward by some recent European studies. ‘A unique aspect of the game,’ they point out, ‘is the purposeful use of the unprotected head for controlling and advancing the ball. Reports of studies of high-level amateur and professional European footballers suggest that extended exposure to the game may be associated with chronic cognitive impairment.

‘It is further postulated’, they add, ‘that multiple subconcussive impacts to the head, such as those involved in repeated heading of the ball, may be responsible for degenerative impairment of normal brain function. Some authors have even suggested that repeated heading of the ball in game or practice situations may be comparable in effect to receiving multiple blows to the head in a boxing match or while sparring.’

Such reports have apparently sent ‘shock waves’ through US youth football communities, with mandatory use of protective headgear proposed as a possible solution. Happily, though, these fears seem unfounded – at least as far as college-age athletes are concerned. For a battery of ‘neuropsychological’ tests, measuring such capacities as orientation, concentration, problem-solving, verbal association, attention and memory failed to reveal any significant differences between the groups.

Even a history of concussion did not appear to predispose to mental impairment, since subjects with a history of two or more concussions were no more likely to have depressed neurocognitive performance that those with no such history. When analysis was performed by sex, the only significant difference found on any of the tests was for the verbal learning test of immediate memory recall. But this was as significant for the controls as for the footballers.

The researchers conclude: ‘Our results indicate that participation in football is safe, at least up to the collegiate level, when considering its effect on neurocognitive function. Neither participation in football nor concussion history was associated with impaired performance of neurocognitive function in high-level collegiate football players with a mean age of 19 years. Although our findings need to be replicated in other settings, these results should provide reassurance that exposure to football during youth and adolescence does not appear to be associated with measurable deficits.’

However, it is clear that football players are at particular risk of concussion, and the researchers suggest that the focus should now be placed on ways to reduce the risk, most especially through ‘quality instruction’.

…But the Risk Appears to Increase with Age

That’s the rather less sanguine conclusion of another American study, which found that footballers performed worse than swimmers on measures of conceptual thinking, with older football players scoring particularly poorly on reaction time and concentration, as well as conceptual thinking.

The researchers, from Florida University and the State University of New York, compared performance in four neuropsychological tests (assessing motor speed, attention, concentration, reaction time and conceptual thinking) in 32 footballers and 29 swimmers. Of the footballers, 26 were college students and six current or former professionals, with a median age of 41.5; of the swimmers, 29 were students and seven veterans (median age 42.68).

The researchers were testing two hypotheses:

• that footballers, particularly older ones, would show poorer neuropsychological test performance than swimmers, who are less likely to sustain sport-related brain injury;
• that the severity of neuropsychological deficits in footballers would correlate with the extent of their participation in the sport – ie the length of their careers and their level of competition.

Their results partly supported these hypotheses, although not all the tests revealed significant differences between the footballers and the swimmers or between old and young footballers.

‘To our knowledge,’ state the researchers, ‘this is the first study to demonstrate a dose-response relationship whereby greater football experience is linked to poorer NP (neuropsychological) test performance, consistent with the hypothesis that playing football places individuals at risk for NP compromise.’

The fact that this dose-response relationship was even stronger when goalkeepers, who rarely head the ball, were excluded from the analysis supports the idea that the deficits detected are caused by football-related head trauma.

The researchers hasten to point out, though, that there is no clear evidence that such impairments, as demonstrated on formal testing, lead to practical difficulties in daily living.

They conclude: ‘The younger groups’ performance leads us to concur with the assertion that, in the absence of frank concussion, younger footballers are unlikely to manifest significant NP impairment. However, the potential eventual consequences of long-continued football participation must be appreciated.’

They suggest that the risks could be minimised by such precautions as using proper size balls, coaching of correct heading technique, availability of adequate on-site care, return-to-play guidelines and annual NP screenings for athletes in head-contact sports.

Am J Sports Med 2002 Mar-Apr 30(2), pp157-162 J Sports Med Phys Fitness 2002 Mar 42(1), pp103-107