miércoles, 1 de abril de 2009
TRUNK STABILITY FOR RUGBY PLAYER
What exactly is trunk stability for a rugby player?
It is the ability to hold good posture of the torso when high loads are applied to it,including occasions such as:
• Running with maximal effort, including acceleration and deceleration.
• Contact, such as tackling, rucking and mauling.
• Set piece play at scrum and line-out.
• Training, in particular with weights.
• Not playing, when sitting, standing and sleeping.
What does the research tell us?
The following extracts were taken from Stuart McGill’s excellent text, ‘Low Back
Disorders: Human Kinetics’ (2002).
• “Achieving stability is not just a matter of activating a few targeted muscles, be
they multifidus, transverse abdominis or any other. Sufficient stability is a moving
target that continually changes as a function of the three-dimensional torques
needed to support postures.”
• “Quantitative data have confirmed that no single abdominal exercise challenges
all of the abdominal musculature while sparing the back.”
• “Generally, preserving the neutral lumbar spine will solve many of the safety
issues, but this depends upon the ability to take the shoulders and hips to extreme
ranges in the range of motion.”
The rugby player’s back.
These are general observations but fairly representative of most rugby players.
• Lordotic (hyper-extended low back).
• Kyphotic (flexed upper back).
• Anterior tilted pelvis.
• Tight hip flexors.
• Externally rotated femur.
• Limited hip ROM (range of motion).
Playing and training with intense effort and with these postural problems can often result in:
• Hyper-mobile lumbar spine (lax ligament support).
• Chronic ‘stiff’ back.
• Very limited ROM.
• Tight hamstrings.
• Tight groin.
• Tight calves.
• Prominent muscle groups/actions.
Can training help with these problems (above)?
One factor that may be linked to alleviating these problems is muscular endurance.
Research suggests that:
• Muscular endurance is related to reduction in back troubles in the non-athletic
population. (McGill, 2002.)
• McGill’s work also suggested that back problems can be alleviated in the large
part by improving and then grooving the motor patterns of the abdominal
• There will be an improved, grooved motor pattern with better muscular
• The ability to use all ‘available’ musculature will be improved.
• Considering the contact nature of the game of rugby, there will be a development
in the ability to co-contract the abdominal wall independently of any lung
ventilation patterns. There is a real need to keep the abdominal wall tight,
independently of the breathing cycle; contraction must not rely on whether you
are breathing in or out.
This is all part of what can be a vicious circle. Poor posture leads to the inactivation of important muscle groups. This gets progressively worse, with elevated back pain and the sequence goes on. If the subject could learn to re-activate the muscles and hold a better posture, McGill has shown a very high rate of pain reduction.