Stretching ain’t stretching!
Most don’t realise this, but stretching does not actually change the length of the muscle!
Instead, it alters the interaction between the nervous system and the muscle. Bundles of muscle fibres are controlled by a nerve, which controls when the muscle fibre bundle contracts and relaxes. This nerve is being fed information from sensors that exist within the muscles and joints, as well as from other parts of the nervous system. This helps create safe and fluid movements in coordination with other muscle bundles.
There are protective mechanisms in place that prevent movements into extremes of range of motion around a given joint – sensors that exist within a motor unit that report back information to the nervous system about the current state of stretch and tension on the muscle. When this becomes too far out of the comfortable range, these sensors engage the nervous system and it in turn prevents the muscle from moving beyond a certain range.
Stretching, massage, foam rolling (self-myofascial release) and movement in general can all alter what the system perceives as threatening or irregular. This is one reason why training through a full range of motion when you use weights is really important, and can improve more than just strength and muscle size – it actually improves mobility (as well as strength in the extremes of range).
This means that there are multiple ways you can attack improving mobility – weight training, mobilisation drills and stretching in its various forms are all legitimate methods that can be combined to produce a result!
It’s also a big reason why the term “musclebound” is total BS! There are plenty of muscular individuals who display amazing flexibility – even pro bodybuilders!
This means that when we’re thinking about improving mobility, it’s usually best to think in terms of improving a particular movement or position. In other words, simply stretching everything in general is cool, but for example, if you’re specifically trying to improve your squat then getting into specific positions that support that goal is going to be most effective for re-calibrating your neuromuscular interface (so to speak!).
It also means that spending too long in one position is not ideal. this runs against conventional logic that says you should always be in neutral spine, or always have your shoulders down and back. The issue is usually not the actual position you’re in in a given moment – it’s that we spend far too long in the SAME position: e.g. sitting in a hunched position at the computer (which necessitates doing the opposite to try and bring the balance back to somewhere in the middle). You could conceivably spend way too much time in the opposite position too – it’s just that no one really does that in day to day life.
The correct approach to mobilisation involves several things – including producing stability (this ‘trick’s the nervous system into allowing more range), using the right stretches/exercises and also using the right amount of volume. Mobility training can be programmed and periodised just like any other form of training!
If you want to maximise your mobility, here’s what you need to keep in mind: train with a full range of motion; perform movements under load (ie resistance training); work hard to get into many different positions and ranges within your training, but prioritise what you need most for your activities; and finally, dedicate enough time each week to produce a change!