The primary focus of this module will be on multimodal injury prevention programmes like the FIFA 11+. These programmes incorporate a range of different exercises and are the best validated injury-prevention strategy. They typically include running, strength and proprioceptive exercises. It is, however, important to realise that there are a variety of different interventions which can be used to prevent injury.
There is an increasing body of evidence that shows that it is possible to reduce the risk of sustaining a hamstring muscle injury. Strategies which have been proposed include different kinds of stretching activities, eccentric strength training, core stability and combinations of these.
- While most coaches and athletes generally believe that stretching is effective, it is not clear whether it does prevent injury. There are no good intervention studies which have addressed this question in elite athletes. One questionnaire-based study, involving thirty English clubs, has suggested that stretching may help reduce injury risk. While it is possible that stretching has a role in preventing injury, it is likely to be substantially less effective than eccentric training.
- Eccentric strength
- Several studies show that eccentric training (Nordic hamstring) reduces hamstring injury incidence in different populations of football players.
The best evidence for the preventive effect of eccentric strengthening is a randomised controlled trial from Denmark comparing the effect of the Nordic hamstring exercise on the rate of acute hamstring injuries in male football players. This study demonstrated that the injury rate was 71% lower in the group that practised the Nordic hamstring exercise. For players with a history of hamstring strains, the effect was even greater, with 86% reduction in injury rates. 14
Similar kinds of eccentric protocols have also been proposed for preventing quadriceps injuries (reverse Nordic hamstring) and a gradual increase in the volume of kicking actions in footballers in critical periods to help to reduce the rate of injury. The optimal intensity of eccentric training programmes is not yet clear.
- Core stability
- Many hamstring injuries occur in trunk flexion during running, in the typical position assumed during shooting and accelerating. Motor control of the lumbar spine and pelvis is essential in the preparation and execution of the different sports movements. Including core exercises in training sessions may also decrease the load in the rectus femoris (quadriceps) and reduce the risk of injury.
- Balance and proprioceptive exercises have also been investigated as a possible injury-prevention strategy. The effectiveness of this type of intervention is not clear with studies showing conflicting results. A significant reduction in ACL injuries in male professional and amateur players was found after balance board proprioceptive training. 15 This data was not corroborated by subsequent studies. Söderman et al. found no preventive effects with the same intervention on the incidence of acute knee injuries in female adult players. 16 While the role of balance training as a stand-alone intervention is not clear, this type of training is widely used. Balance exercises are part of comprehensive neuromuscular warm-up programmes, like the FIFA 11+, which have clearly been shown to be effective in reducing injuries.
- Strapping and bracing
- Strapping and bracing can be effective strategies. They have not been shown to be good strategies for primary prevention. The best evidence is for the prevention of ankle sprains – in players with a past history of ankle instability. In these players, taping or bracing the ankle (to limit inversion) can reduce the risk of subsequent ankle sprains by about 50%.
- The influence of loading and training volume has been identified as a risk factor for injury. This is especially true in adolescent and youth players. Too much loading, and sudden changes in loading, have been associated with an increased risk of injury. Times when loads typically increase include during the pre-season, when returning from injury or when players enter an elite training environment. It is especially important to have a carefully designed training programme during these times.
- Fitness and conditioning
- Muscle injuries occur most frequently towards the end of each half. Given the demanding nature of football, it has been suggested that this is due to fatigue. 17 As a result, a low level of fitness may be an injury risk factor for players. Improving fitness may therefore reduce the risk of injury. It is, however, possible that increasing fitness may be a risk factor for injury. Players with greater physical fitness typically work harder and, as a result, may be more likely to become injured. Common sense would, however, dictate that appropriate conditioning is important.
Dr Mark Fulcher
Sport and Exercise Physician