Background Hamstring injuries are among the most common non-contact injuries in sports. The Nordic hamstring (NH) exercise has been shown to decrease risk by increasing eccentric hamstring strength.
Objective The purpose of this systematic review with meta-analysis was to investigate the effectiveness of the injury prevention programs that included the NH exercise on reducing hamstring injury rates while factoring in athlete workload.
Methods Two researchers independently searched for eligible studies using the databases: the Cochrane Central Register of Controlled Trials via OvidSP, AMED: Allied and Complementary Medicine via OvidSP, EMBASE, PubMed, MEDLINE, SPORTDiscus, Web of Science, CINAHL and AusSportMed from inception to December 2015. The keyword domains used during the search were Nordic, hamstring, injury prevention programs, sports, and variations of these keywords. The initial search resulted in 3242 articles which were filtered to five articles that met the inclusion criteria. Main inclusion criteria were randomised controlled trials or interventional studies, use of an injury prevention program that included the NH exercise while the primary outcome was hamstring injury rate. Extracted data were subjected to meta-analysis using a random effects model.
Results The pooled results based on total injuries per 1000 hours of exposure showed that programs that included the NH exercise had a statistically significant reduction in hamstring injury risk ratio [IRR] of 0.490 (95 % confidence interval [CI], 0.291 – 0.827, p = 0.008). Teams using injury prevention programs that included the NH exercise reduce hamstring injury rates up to 51% in the long term compared with the teams that do not use any injury prevention measures.
Conclusions This systematic review and meta-analysis demonstrates that injury prevention programs that include the NH exercises decrease the risk of hamstring injuries among soccer players. A protocol was registered in the International Prospective Register of Systematic Reviews, PROSPERO (CRD42015019912).
The aim of this systematic review with meta-analysis was to investigate the effectiveness of the injury prevention programs that included the NH exercise on reducing hamstring injury rates while factoring in athlete workload.
There is strong evidence that training programs that include the NH exercise decrease the risk of hamstring injuries by up to 51% in the long term compared with usual warm-up or training programs.
The current evidence suggests that the NH exercise alone or in combination with injury prevention programs is effective for preventing hamstring injury.