This systematic review and meta-analysis provides further evidence that incorporating Nordic hamstring exercises (NHE) into an injury prevention programme reduces the risk of hamstring injuries by more than half – in different sports and at different levels of sport1.
Hamstring injuries are the most common muscle injury across varying sports (including football). They can cause a prolonged absence from sport and have a high rate of recurrence. Fifteen relevant studies were included in this study (cohort, randomised and non-randomised control trials). These studies used NHE as the intervention or included NHE as part of a larger prevention programme. Data was analysed for 8459 individuals including 525 hamstring injuries, across a range of studies with clinical heterogeneity. Two studies reviewed female athletes, while the remaining thirteen involved male athletes. Only three studies did not involve football players (these involved rugby, baseball and Australian football) with athletes ranging from 18-40 years.
The positive effect of NHE remained even when removing studies at high risk of allocation, detection and attrition bias from the analysis. The reviewers also looked at the randomised controlled trials alone, and found the overall effect changed only minimally. There was a large variation in the training protocols using NHE amongst the studies, however the overall effectiveness remained strongly positive.
Interestingly there was no significant reduction in hamstring injury using NHE in the two studies involving female athletes. This may have been influenced by the lower rates of hamstring injury in female players, however further analysis with female populations may be useful. Furthermore the studies varied between the hamstring injury being the index injury (four studies), recurrent injury (four studies), or not reported (seven studies), therefore the risk reduction associated with index versus recurrent injury was unable to be commented on. This would be worth future investigation to apply NHE in the most effective manner as an injury prevention tool.
1van Dyk N, Behan FP, Whiteley R. Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries: a systematic review and meta-analysis of 8459 athletes. Br J Sports Med 2019;0: 1-10.