A bit of a stretch?

If you're already a runner, I'm sure you will have heard various opinions about stretching. You may have tried out different types of stretching. But you may still be confused about what you should or shouldn't be doing - I certainly was! And if you're new to running, then you may want to find out more about it.

So first things first, there are 3 types of stretches: static, ballistic and dynamic. Static stretches involve stretching and holding the muscle for a duration up to 30s at a time, up to the range of motion and no further. Dynamic stretches mean controlled movements to warm up the muscles. Ballistic stretches are about uncontrolled bouncing that take the muscle beyond the normal range of motion. Each have a role to play, except in my view ballistic stretches, which have now been associated with a high risk of injury.

So, when to use which?
 

Keep static stretches for cool down

Static stretches are best used during cool down for a number of reasons:

1. First of all, the obvious: if you try and stretch cold muscles, you are risking an injury.
2. Although this type of stretch is a good way to address muscle tightness because it works on lengthening the muscle and can help prevent injury (a 2005 study showed evidence of an associated reduction in hamstring injuries), this is only true of static stretches performed AFTER a run. A research study on static stretches performed by army recruits PRIOR to exercising show no evidence of a reduction in risk of injury.
3. Another argument for avoiding the static stretches before a run is that it may impair performance by affecting running economy, as highlighted in a 2015 study. The reason behind this is that static stretches reduce the stiffness in the contractile muscle and attached tendinous structures, which is beneficial to running economy (as it happens, flexibility is not something most runners should worry about, quite the opposite).

Also, if you were hoping these post-run static stretches would be helping with Delayed Onset Muscle Soreness (DOMS), you're out of luck. A study by Herbert and Gabriel published by the British Medical Journal showed that stretching did nothing to help with DOMS.

Another note on flexibility, which as I said above is not something most runners need to work on, as it becomes at some point detrimental to running economy: there are some exceptions to this. If your poor flexibility restricts you from having the full range of motion (ROM) then this would affect your biomechanics and ultimately your running economy. An example of this would be having too tight hip flexors that do not allow normal hip extension. This is typical of runners who spend most of their day sat at their desks. In that case working on flexibility of these hip flexors would help improving your biomechanics and then ultimately running economy so these static stretches may be a worthwhile investment.

So yes to static stretches, but only post-run!

Warm Up with a Run (or use Dynamic Stretches as an Alternative)

Based on the above findings and the previously mentioned study, the current recommendation is to use a progressive low intensity warm-up run to fire up the muscles that will be mobilised by running.

However if you're still keen to incorporate stretches into your warm-up, ensure you use dynamic stretches only. I am not much of a pre-run stretcher myself but some of the dynamic stretches I occasionally use can be found here.

Happy running!!