The Science of Stretching & Flexibility

Should you incorporate a regular flexibility programme?

There are various opinions on the internet around stretching.  Some say do it before activity, some after and some not at all.  We asked The Strength Temple Director, Doctor and Sports Medicine Physician, Dr Dan Roiz de Sa about it.  He has provided the following information and advice; it’s the current thinking on stretching and joint mobility from a professional, not a google warrior!  Over to you Dr Dan….

Let’s discuss the background of flexibility and why we advocate this as part of our #7Pillars approach to overall wellness.  I think it’s always good to start with a definition, so let’s begin there.

What do we mean by flexibility? It is the ability to move a joint (or group of joints) through the optimal range of movement intended for that joint (or group of joints).

Some people have an inherent flexibility that is very much more than others and are described as being hyper mobile.  This condition normally has its foundations in that person's genes. For most of the rest of us, if we lack sufficient flexibility we are hypo mobile and are unable to get a joint to have the degree of motion for which it is designed.

Joints can be limited in their range by the size and shape of the harder bony structures that make up the shape of the joint.  If this is the case there is not a lot that we can do about it on a day to day basis but what we can affect are the softer tissues and connective tissues that surround or cross these joints.

There is considerable variation in expected ranges of motion for different joints with established guidelines in the scientific and medical literature, but what we really want to know is how much flexibility is sufficient and sufficient for what? Clearly, the flexibility required by a gymnast is very different from that required by an average person to carry on with the activities and pastimes of normal daily living without undue difficulty or injury. Therefor, the question about what is an adequate range of flexibility is a relative one and we all need to consider what we need for daily living, our work, our hobbies, pastimes and exercise interests.

I’d suggest that if you find you’re pushing yourself, or modifying movement to complete certain tasks, then you could do with increasing your flexibility.  By certain tasks I mean sporting activities or simply putting your socks on in the morning.  Conversely, if you have full flexibility with a good range of movement then a flexibility maintenance regime will be in order, which draws on the old adage that if you don’t use it, you lose it!

The use of stretching techniques and programmes as a means of addressing lack of range of movement or flexibility is widely advocated for both health and fitness maintenance.  It is also integral to the design of many training programmes for rehabilitation from injury. There are many trainers, authors, coaches and athletes who advocate a stretching programme to increase range of movement. The theory being, that by incorporating this daily activity, the soft tissues, that is to say the connective tissues around a joint, will change their properties in a beneficial way.

The tissues we are talking about are those making up ligaments, joint capsules, layers of fibrous tissue (or fascia) and the tendons and muscles that move the joints.  The connective tissues really targeted by flexibility programs are these dense collagen connective tissues which have very high tensile strength and are therefore rather resistant to elongation.

The other area that flexibility work targets is the muscles that contract to move a joint and the tendon that imparts this force (from the muscle) to the bones; this can also be called the musculotendinous unit.

The many reported benefits of stretching include enhanced performance, avoidance of joint dysfunction, less muscle soreness and reduced musculotendinous unit injury and scar tissue formation.

Being a hard nosed scientist at heart I find it difficult to find good evidence for all these claims, but there is some to suggest that there might be a reduction in injury prevalence. It is certainly something I have incorporated into my daily routine and anecdotally I have noticed a world of benefit.  Bottom line is - we recommend stretching at The Strength Temple.

How does stretching work? What is it that we are trying to do when we stretch?

The answer to these questions relates to soft tissue and nervous system physiology. When we apply a stretch to tissue, we are applying a force that wants to elongate that tissue in a way that it will initially resist.  The effects of stretching can be categorised into neural (nervous system), plastic and elastic effects.

Neural: Stretch Reflex

This starts from a fancy littlestructure in our muscles called the muscle spindle, which results in a protective muscle contraction depending on the rate or magnitude of force applied. This is what your Doctor or Physio is testing when they hit your knee with that little hammer!

Neural: Inverse Stretch Reflex

Number two is the inverse stretch reflex which applies to prolonged stretching and contraction of a musculotendinous unit.  This reflex is initiated by another superb little piece of kit we have in our muscles properly known as the Golgi tendon organ.  A prolonged stretch of this structure (at least 6 if not 20 seconds) results in a dampening or reduction in nerve impulses telling a muscle to contract.  It is essentially recalibrating and resetting the nervous system response to a muscle being elongated. How amazing is that?

Neural: Nervous System Control of Pain

This is achieved via pressure sensors in the muscle which assist in pain regulation. With a prolonged stretch these last two reflexes allow relaxation of the musculotendinous unit and reduction in pain.  If you do this repeatedly then it is suggested that by inducing changes in nervous system excitability, we get an increased tolerance and an increased range of movement.

Elastic and Plastic Effects of stretching

These are benefits to the tough non-contractile elements around joints. Constant stretching will result in plastic deformation; in other words increased tissue length. When this tissue is around a joint or combination of joints that means increased range.

Conclusion

Stretching, providing you are not hyper mobile should therefore be looked at as a component of your whole body maintenance regime. It has benefits and not just for gymnasts or elite athletes. It will result in you feeling better providing it is done properly, in a controlled and logical way. There are many methods to approach flexibility work; we will discuss some of these in future insights.

Bottom line - do your stretching.  We show you how to do it safely and correctly in our #7Pillars Program - due for release end Summer 2016!

Oh, and don't forget to #respectyourtemple

Dr Dan RdS