What factors are involved in hamstrings injury?
Hamstrings injury is the most frequent muscle injury in sports that require high speeds, such as football, rugby or American football.
The ischiosural muscles are one of the most common groups of muscles to get injured, especially in sports which involve changes of direction and speed (Bahr, Clarsen, & Ekstrand, 2018; Hägglund, Waldén, & Ekstrand, 2005). The incidence of this kind of injury in professional football has increased annually by 4% since 2001 (Ekstrand, Waldén, & Hägglund, 2016). Therefore, medical staff, coaches and trainers try to develop prevention programs which aim to reduce its incidence. An exercise very much used in these programs is the Nordic curl (NHE).
Recently, a study (van Dyk, Behan, & Whiteley, 2019) published in the British Journal of Sports Medicine has analyzed whether including this exercise in a prevention program really reduces the injury rate in the ischiosural muscles. After evaluating 15 studies, 8459 athletes and 525 injuries, the analysis showed that including the NHE reduces up to 51% the risk of injury.
Based on such beneficial results and considering the high eccentric component of this exercise, one of the objectives of the S&C coaches and sports therapists, should be developing an adequate progression of the exercise (see Table) according to the player’s level and the context of the season. To sum up, the NHE within a prevention program adjusted to the athlete’s level could significantly reduce the injury rate in the ischiosural muscles.
Bahr, R., Clarsen, B., & Ekstrand, J. (2018). Why we should focus on the burden of injuries and illnesses, not just their incidence. British Journal of Sports Medicine, 52(16), 1018–1021. https://doi.org/10.1136/bjsports-2017-098160
Ekstrand, J., Waldén, M., & Hägglund, M. (2016). Hamstring injuries have increased by 4% annually in men’s professional football, since 2001: a 13-year longitudinal analysis of the UEFA Elite Club injury study. British Journal of Sports Medicine, 50(12), 731–737. https://doi.org/10.1136/bjsports-2015-095359
Hägglund, M., Waldén, M., & Ekstrand, J. (2005). Injury incidence and distribution in elite football—a prospective study of the Danish and the Swedish top divisions. Scandinavian Journal of Medicine & Science in Sports, 15(1), 21–28. https://doi.org/10.1111/j.1600-0838.2004.00395.x
van Dyk, N., Behan, F. P., & Whiteley, R. (2019). Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries: a systematic review and meta-analysis of 8459 athletes. British Journal of Sports Medicine, 53(21), 1362 LP – 1370. https://doi.org/10.1136/bjsports-2018-100045
An article published in The Orthopaedic Journal of Sports Medicine —in which members of the club’s medical services participated— now suggests to consider the detailed structure of the area affected, and treating the extracellular matrix as an essential player in the prognosis of the injury.