Thursday, 4 May 2017

Stretching and the role of fascia

I'm working my way through Fascia in Sport and Movement, edited by Robert Schleip, reading the chapter on fascia as sensory organ. Fascia is a fascinating subject. It is an intricate and historically overlooked anatomical and physiological feature. These days there is more and more research being undertaken to explore the nature and function of what appears to be the largest sensory organ of the body (p31). I'm just reflecting on this paragraph:
Stimulation of the Golgi receptors tends to trigger a relaxation response in skeletal muscle fibres that are directly linked with the respectively tensioned collagen fibres. However, if tendinous extramuscular are stretched in a condition in which they are arranged in series with relaxed muscle fibres, then most of the elongation will be 'swallowed' by the more compliant myofibres. In this way, the respective stretching impulse may not provide sufficient stimulation for eliciting any muscular tonus change (Jami, 1992). A practical conclusion may be that a stretching impulse, aimed at reaching the tendinous tissues, may profit from including some moments in which the lengthened muscle fibres are actively contracting or temporarily resisting their overall elongation. (p33)
My first thought was isn't this what we do when we apply MET or PNF? In both those approaches to stretching we use the Golgi Tendon Organs to elicit a relaxation phase in the target muscle by contracting it against a resistance and 'turning off' the muscle spindles. But maybe this also explains why, having stretched a muscle it can quickly return to its shortened state. Perhaps it is simply not enough to target the compliant fibres, needing in addition to target those less compliant fibres. I don't know, and it definitely needs more thought. There are many other possible reasons why, after applying all our techniques and skills, some tissue simply refuses to respond as we would like. But it does look like a deeper understanding of an appreciation for the role of fascia could open up a whole new world of possibilities!

One of those possibilities that came to mind was to experiment with stretching by adding a small degree of stretch during the contraction phase. It's just a wild idea at the moment, and may prove totally fruitless. Even as I think about it, I wonder how you could do this in practice-stretch an already contracting muscle. I shall have to experiment on myself!