This article is available in full from the British Medical Journal Web Site.
By Odd-Egil Olsen et al – Sports Trauma Research Center, University of Sport and Physical Education, Oslo, Norway
BMJ 2005;330:449 (26 February), doi:10.1136/bmj.38330.632801.8F (7 Feb 2005)
Introduction
Regular physical activity reduces the risk of premature mortality in general and of coronary heart disease, hypertension, colon cancer, obesity, and diabetes mellitus in particular.

However,participation in sports also entails a risk of injury for allathletes, from the elite to the recreational level. Studies from Scandinavia document that sports injuries constitute 10-19%of all acute injuries seen in emergency departments, and themost common types are knee and ankle injuries. Serious kneeinjuries, such as injuries to the anterior cruciate ligament,are a growing cause of concern. The highest incidence is seenin adolescents playing pivoting sports such as football, basketball,and team handball. In these sports, women are three to fivetimes more likely to contract a serious knee injury than men.
Injuries to the anterior cruciate ligament may require surgery,always entail a long rehabilitation period, and drasticallyincrease the risk of long term sequelae. Although treatmentmethods have advanced notably, there is no evidence to showthat repair of a ruptured anterior cruciate ligament or isolatedcartilage lesions prevents early development of osteoarthritis.

Effective methods for preventing injuries therefore need to be developed. Some studies report promising results, indicating that it may be possible to reduce the incidence of knee and ankle injuries among adults and adolescents. However, these studies are small and mainly non-randomised, with important methodological limitations. Prospective randomised intervention studies are therefore needed, especially among children and adolescents, to assess the efficacy of interventions aiming to reduce injuries. We conducted a randomised controlled trial to investigate the effect of a structured programme of warm-up exercises used to prevent acute injuries of the lower limb in young people playing sports. To minimise overlap within clubs, we used a cluster design.
Conclusion A structured programme of warm-up exercises can prevent knee and ankle injuries in young people playing sports. Preventive training should therefore be introduced as an integral part of youth sports programmes.
Here is an interesting article on proprioception and ankle rehabilitation.