Hamstring injuries are common in running-based sports such as AFL, rugby, soccer, hockey and athletics.
In our Brisbane sports physiotherapy clinic in Greenslopes, we see a few every week.
The thing about hamstring injuries is that are are no easy ways – no screening tests or exercises – that are accurate enough to predict who will get injured.
What we do know is that you’re at greater risk if you’ve had a hamstring injury before and/or are over the age of 25 years of age.
Research has also shown that lower levels of eccentric strength increases your risk of hamstring injury. So if your muscles aren’t as used to lengthening under load, they’re more likely to tear. The classic example of the middle-aged person tearing their hamstring while playing touch football exists for good reason: they’re right in the at risk category. Being over 25 and with generally lower tolerance for lengthening their muscles under load (eg while picking up a ball or breaking through a line), they can easily over-exert and cause a torn hamstring (and a great deal of pain).
Interestingly, professional footballers with previous hamstring strains have also been shown to be more than 7 times likely than uninjured players to sustain a new strain (Thorborg, 2017).
This information suggests that improving hamstring eccentric strength, as well as fascicle length, can reduce the risk of hamstring injury. This means improving the strength of muscles as they lengthen. A good example of an eccentric movement is stretching the calf as your foot lands while running.
For hamstring strengthening, and to reduce the risk of tears, an exercise known as the ‘Nordic exercise’ can be used with good results.
The Nordic exercise specifically targets hamstring eccentric strength and fascicle length (fascicles are bundles of muscles that connect muscles to bones).
Illustration of Nordic Exercise for reducing chances of a torn hamstring
Nordic Hamstring Exercise Training Protocol Table
The Nordic exercise protocol should be implemented with gradual increase as outlined in the table below. Initially, some athletes may require the use of a band around the hips to help assist the exercise.
Studies show reductions in hamstring injuries (eg torn hamstrings) by 70% when completing the Nordic protocol. However, a survey of 50 professional soccer teams (EPL) over 3 years resulted in a very poor compliance rate of only 8% (Thorborg, 2017).
Therefore, it’s important that for the best chance of avoiding a hamstring injury while playing sport, the Nordic protocol is implemented to perfection and continued throughout the season (once a week) to be effective in reducing hamstring injuries.