Most of us are already aware that our muscles like to be eccentrically loaded (1) prior to producing force for function and performance (I hope) however even the analogy of eccentric loading (deceleration) and concentric unloading (acceleration) is still only part of the picture (all be it better than how I originally learnt my muscle function!).
Any trainer/therapist training clients/patients for function or performance needs to understand the implications of how muscles actually function in movement. We at KiMotion are aware that the complexity of muscle function is still being researched however it is known that all muscles can be working eccentrically, concentrically and isometrically at the same time (2) within different parts of the same muscle at different joints, or econcentrically!
During forward foot strike in walking gait:
Soleus will eccentrically load from the bottom up due to ground reaction force and top down from gravity and the mass and momentum which causes the calcaneus to evert in the frontal plane and eccentrically load soleus.
During the stance phase of gait the mass and momentum of the body moving forward creates ankle dorsiflexion , which eccentrically stimulates the soleus further. As this eccentric contraction builds up, just prior to heel lift, the soleus utilises its sagittal plane eccentric loading power at the ankle to concentrically invert the calcaneus in the frontal plane and extend the knee in the sagittal plane thus contracting econcentrically!
Big Deal I hear you say what does that mean to me in practise! Well if function and performance are goals to be achieved the training principle of specificity first needs to be applied and adhered to. In essence ‘how you train is how you’ll adapt’.
Knowing that our muscles can work econcentrically means, to get full function from them in our training we need to apply adaptations to our movements and exercises to enable them to experience and imprint these new contractions and the required motor patterning within our neuromuscular system.
Of course we can apply multiplane movements that will encourage a variety of econcentric contractions required and at KiMotion using the Gray Institute principles we have further developed our ‘Critical Squat 162′.
In most cases a small adaptation is all that is required (i.e internal or external rotation of the feet – Left or right stride stance) to encourage a variation of econcentrics and a new motor pattern, which is better for enabling the body to cope with the variations of movement the human can take during function and performance.
KiMotion believe that this form of training will support traditional methods of strength and conditioning and perhaps more importantly prepare your reactive muscular system to better cope and protect you when you go beyond the traditional range of motion in activity!
The picture below shows how foot position adaptation in the 3 planes ( an external rotation in the transverse plane has been chosen) can provide a variety of complex econcentrics and with adding arm (top down) drivers as well can provide one adaptation of what we call ‘Critical Squat 162′.
There are many other adaptations that can be considered as well as different bottom up and top down drivers without even considering the environment!
Makes you wonder why we get stuck with the same movement/exercise and for function you need to Critical Squat 162!
You can learn the principles of our ‘Critical Squat 162′ HERE!
2nd Ed, Lippincott, Williams and Wiliams 2002; 6(37) 545
Ward R C, Editor
Gary Gray, Dr David Tiberio, Doug Gray