Updated: May 21
Hamstring injuries are one of the most common muscle injuries seen in sport that involves some form of maximal speed running. As such there has been a lot of interest in how we prevent this type of injury that can be difficult and troublesome to recover from.
In recent years a lot of attention has focused on the Nordic hamstring exercise as a method of strengthening the hamstrings and reducing the injury rates.
Eccentric strength and hamstring injury prevention
The nordic exercise has a strong eccentric strengthening component, that is to say it helps strengthen the hamstring as it lengthens against a force. The middle diagram demonstrates how eccentric contraction works.
This eccentric capacity of hamstring muscles is required to offset the concentric action of the quadriceps during terminal swing in running and sprinting .
Any deficits in this eccentric strength can result in increased injury risk with maximal and near maximal sprinting.
It is during this lengthening / eccentric action of the hamstring that most injuries occur.
So is the Nordic hamstring exercise it as effective as people hope ?
In 2019 there was a review conducted by Van Dyk et al that looked at the rate of hamstring injuries and using the exercise as a preventative measure. The review included results from almost 8500 athletes of varying levels.
What did this study show ?
Over the course of using the nordic exercise there was an overall reduction of 50% in hamstring injuries.
But are Nordics the be all and end all in hamstring strengthening and prevention ?
Looking at how the nordic hamstring exercise affects the hamstring muscle group the following has been found;
Muscle activity was highest during the middle phase of the exercise (that is 60-31º), and remains significantly elevated even at more extended joint positions (30-0º).
So it's very useful for that range of motion and strengthening the eccentric qualities of the muscle. However other exercises need to be incorporated to ensure it is injury resistant and strong all the way through its available range of motion.
As the saying goes you're only as strong as your weakest link.
For effective hamstring prevention other areas of physical conditioning that need to be addressed include;
Trunk and hip strength.
Hip flexor tightness.
Higher CV fitness so that fatigue plays less of a role.
Incorporation of maximal and sub maximal speed training.
Velocity specific hamstring exercises for the hamstrings.
How to do you do Nordic exercises at home ?
Not the easiest exercise to do without equipment however here are some great options from the wonderful world of youtube.
A Staged progression for the nordic hamstring exercises.
With this exercise its important to progress up to the higher levels and not jump right in, (as i found out yesterday). This link will take you to examples of strengthening exercises for the hamstrings.
The video below shows ways to reduce the difficulty of this exercise and build yourself up to unassisted Nordics.
There's more to hamstring rehab than this exercise , but it does form a significant part of successful return to action.