Sports have long been the greatest single cause of injury in the western world, though as a cause of accidental fatality it remains comparatively infrequent. Not all such injuries are inevitable, however, or inseparable from the sporting activity which give rise to them.
A paper in a recent British Medical Journal demonstrates that it is possible for adolescent female soccer players to avoid nearly two-thirds of the anterior cruciate ligament injuries to the knee to which they are susceptible, by the simple expedient of performing a 15-minute neuromuscular warm-up exercise before the beginning of a match.
The study was carried out with characteristic thoroughness in Sweden, where 309 clubs with adolescent female players were randomly allocated to those whose players performed the warming-up exercises under the direction of a trainer and those whose players did not. The rate of cruciate ligament injury was calculated over the following season of seven months.
Seven of 2479 players who performed the exercises had such an injury in the course of the season, while 14 of 2085 who did not perform them were injured in this way.
Assuming — as seems likely — that each player played twenty matches during the season, this means that 12,395 hours of exercise had to be performed to avoid about 8 cruciate ligament injuries, that is to say 1,565 hours per injury avoided. There is, of course, no objective method of determining whether the effort was worth it; it depends on the scale of values employed. What would the players who exercised have been doing if they had not done their exercises? Chatted about their boyfriends? This might surely seem a more agreeable way to spend fifteen minutes.
To avoid a similar number of cruciate ligament injuries boys would have to exercise for even longer, for they are not so susceptible to such injuries in the first place.
Curiously, the exercises did not protect against other knee injuries deemed to be serious, of which there were 19 in the exercise group and 17 in the control group. Nor was the overall rate of acute injury of the knee (serious and non-serious) reduced: it was 48 in the exercise group and 44 in the control group.
Assuming what may not be entirely true, that knee injuries are randomly distributed in the population of female adolescent soccer players (that is to say they do not have individual differences in their susceptibility to them), the chances of an adolescent female soccer player suffering an acute knee injury over five seasons is about 10 percent, and slightly more than 5 percent for a serious knee injury. This is a very high risk: it is even possible that drivers who habitually drive while over the limit get away with it more often than that.
Of course, drunk drivers injure people other than themselves, but so do soccer players. It is, after all, in tackles that most cruciate ligament injuries on the field occur; and while it is true that soccer injuries very rarely kill, a cruciate ligament injury can lead to a lifetime of pain.
The case for banning adolescent female soccer on grounds of health and safety, then, is clear, especially in those countries in which, unlike Sweden, there is no doctor or physiotherapist on call to treat the injured. What other activity would be tolerated that had so high a risk of painful or serious injury? And what is true of soccer is true of virtually all sports, so many of which end in pain and injury. In a world in which thousands of children die of diarrhoeal diseases, why should so many medical resources be diverted to treating what are, after all, self-inflicted injuries?