Hamstring strains are common injuries in sports. They represent the most common injury in sports like soccer and track, accounting for up to 12-16 percent of injuries. Given the large incidence, and that once injured you are at a greater risk of re-injury, many teams commit time and effort in attempting to prevent hamstring strains. One method that has been shown over and over again to prevent hamstring injuries is the Nordic Hamstring Exercises.

Nordic hamstrings are important because research has been done to show they prevent hamstring strains in those without previous injury and those athletes recovering from injury. Other methods have had conflicting data. It is reasonable to expect that improving eccentric function (contracting the muscle while it stretches) of the hamstring may reduce hamstring injury risk—as eccentric actions are the cause of hamstring injuries. This has been shown with video analysis of injuries.

Studies have shown that eccentric strength training with Nordic hamstring exercises (combined with a warm-up dynamic stretching) reduced hamstring strain risk, whereas flexibility training program (static stretching, e.g. sit-on-the-ground stretching) was ineffective. This is likely due to the inability of the "flexibility program" to positively influence the length-tension relationship of the hamstring in the same way as the eccentric strength training. The clinical utility of eccentric training for flexibility and its role in promoting proper hamstring function are part of the effectiveness of doing Nordic Hamstring Exercises.

Almost two-thirds of hamstring injuries might be prevented by doing these exercises. This was seen in more than half a dozen studies. It is simple to do, but challenging. The exercise was first noted in an exercise for health book in the late 1800s.

To do the exercise: After warming up, kneel on the ground (a pad helps), the ankles need to be secured either with a spotter or a couch type item. Next, lower yourself to the ground as slowly and smoothly as possible, with hands by your side. You should lean forward so that your chest approaches the ground. Use your hamstrings to slow your forward momentum until you can no longer resist the pull of gravity. Use your arms and hands at that point to stop your fall (don't smash your face). Allow your chest to touch the ground, and then push yourself back upright to the starting position to repeat the exercise.

The Oslo Trauma Research Center recommends this Nordic Hamstring Exercise four-week training protocol:

Week 1: The subject is encouraged to resist falling as long as possible - twice per week, two sets of five exercises with a break in between sets.

Week 2: Subject tries to reduce lowering speed - twice per week, two sets of six exercises with a break in between sets.

Week 3: Subjects can resist falling even longer, and for an increased number of repetitions - three per week, three sets of six exercises with a break between sets.

Week 4: Load on the subject increases by allowing more speed in the start phase, as well as another gradual increase in repetitions - three per week, three sets of eight exercises with a break between sets.

Hamstring strains can be a long-lasting problem and they can put you on the injured reserve for a long time. Start your Nordic Hamstring Exercises today to help protect your legs tomorrow. Preventing hamstring injuries is easy.

Recommended additional reading:

1: Brukner P. Hamstring injuries: prevention and treatment-an update. Br J Sports Med. 2015 Jun 23. pii: bjsports-2014-094427. doi: 10.1136/bjsports-2014-094427.

2:  Guillodo Y, Here-Dorignac C, Thoribé B, Madouas G, Dauty M, Tassery F, Saraux A. Clinical predictors of time to return to competition following hamstring injuries. Muscles Ligaments Tendons J. 2014 Nov 17;4(3):386-90.

3: Hamilton B. Hamstring muscle strain injuries: what can we learn from history? Br J Sports Med. 2012 Oct; 46(13):900-3. Epub 2012 Mar 29. Erratum in: Br J Sports Med. 2012 Nov;46(14):1023.

4: Heiderscheit BC, Sherry MA, Silder A, Chumanov ES, Thelen DG. Hamstring strain injuries: recommendations for diagnosis, rehabilitation, and injury prevention. J Orthop Sports Phys Ther. 2010 Feb;40(2):67-81. doi: 10.2519/jospt.2010.3047.

5: Woods C, Hawkins RD, Maltby S, Hulse M, Thomas A, Hodson A; Football Association Medical Research Programme. The Football Association Medical Research Programme: an audit of injuries in professional football--analysis of hamstring injuries. Br J Sports Med. 2004 Feb;38(1):36-41.

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