Over the years, we have seen a dramatic increases in body mass, strength and power which has resulted in larger magnitudes of force development. This has perhaps been driven by the strong association seen between teams containing the largest players and success in the professional game.
Perhaps unsurprisingly, rugby union carries a comparatively high risk injury when compared with other sports. Tackle based sports such as rugby exposes the cervical spine to potentially injurious forces, which are absorbed by the musculoskeletal tissues.
While the relatively few catastrophic cervical injuries garner the most research and media interest, it has been suggested that the cumulative effects of these continuous shear and compression forces can have great impact on range of motion and muscle function of the cervical spine.
This may impair the spinal reflexes that act to stabilise and protect this vulnerable region, perhaps predisposing to further injury. Head and neck injuries account for around 30% of all rugby injuries. Strengthening of the neck is a sensible method of mitigating neck injury, while post-injury muscle strengthening is an effective rehabilitative tool, and is a primary treatment for neck pain.
The neck and the scrum
Why do we train the muscles of the neck?
In the context of the scrum, when engaged, its important that the player maintains their position as a great amount of force is being transmitted head down (axial loading). There are no muscles to train in this “head down” position as it is purely your vertebrae and inter-vertebral discs. However, you can training your neck stabilisers – the flexors, extensors and side-flexors so that you stay in this position (15 degree of neck flexion).
As the opposition scrum forces against you, they will try to disrupt your position.
If your neck is forced into a rotated position, you are 25% weaker at the neck in this position. If you are forced into full neck flexion, with all those forces, that can cause severe injury as well as compromising the scrum.
Consider the player as chain, and weakness in the chain will compromise the whole function of the individual and of the scrum.