In part 1 we discussed common lower limb injuries sustained by long distance runners and also highlighted the fact that pronation is often blamed for these injuries. As a consequence, shoes are specifically marketed as anti-pronation and inserts are often encouraged. In part 2, we ask whether pronation is really such a bad thing?
The Benefits of Pronation
One of the simple benefits of pronation is shock absorbancy. As your foot strikes the ground, the inwards rolling on the foot allows the dispersion of energy, thereby reducing the shock. Aside from shock absorbancy, pronation can also assist performance by storing energy and using it to generate propulsion.
In the last blog we discussed the muscles which ‘control pronation’, these muscles can also be used in a propulsive manner, using stored energy in an elastic manner. Look at the video clip below and watch the foot movement as it strikes the ground. What you are seeing largely is ‘ankle eversion’ as opposed to pronation. Pronation is the rolling forwards from heel to big toe, ankle eversion refers to the inward collapse of the ankle which can be clearly seen in the last 2 frames..
Elastic / Plyometric Energy
Hopefully you saw clearly the inward collapse of the ankle under weight.. it looks almost uncomfortable and it looks like bad technique. However, it didn’t seem to do Samuel Wanjiru any harm as he broke the world half marathon record aged only 18 and went on to claim gold at Bejing Olympics in the marathon.
The muscles which control the pronation/eversion movement (discussed in part 1) are stretched as the foot collapses inwards and are able to store elastic energy. That stored energy can then be used to provide propulsion as the muscles ‘spring back’ to their original shape. The ability to store and generate energy in such a way is governed by individual tendon structure and it deteriorates with age as tendons lose elasticity.
Pronation the Performance Enhancer
I’ll stick my neck on the line here and state that Samuel Wanjiru would not have broken the half marathon record if we had inserted an orthotic into his shoe which prevented the pronation / eversion movement you saw in the video. The movement created the elastic energy needed to propel him at such speeds and without it, performances would have suffered.
Go Forwards and Pronate??
That’s not quite what I’m saying.. but the point I am making is that pronation is not necessarily a bad thing. Some running shops and podiatrists conducting gait analysis, upon identifying that a runner pronates, make the snap judgement that the runner requires an ‘anti-pronation shoe’. It would be wrong to make such assumptions and will have a potentially negative impact upon performance.
Some Things to Consider
1. If a runner has no injury history (in particular lower limb) and they visit a shop to be told that they pronate and should therefore wear anti-pronation shoes, that should be seriously questioned!
2. Based on age and tendon structure (varies each individual), some runners will be capable of pronating excessively and rarely suffer injury as a consequence.
3. If you have an injury which is caused by pronation / eversion, your first port of call should be rehab and conditioning so the tissues can handle the movement, store elastic energy and provide propulsion. Don’t instantly take the easy option and purchase inserts. If your injury is chronic, there will be cases where inserts are necessary as this is your only option to continue enjoying running.
4. The video plays extremely slowly, in real time the pronation / eversion movement is ‘super quick’. The stretch and energy return occurs within hundredths of a second as the foot ‘bounces’ on the ground. When you are doing rehab you should consider this, calf raises or lowering are all well and good, but the movement is slow and controlled, unlike reality. You need to include plyometric exercises in the rehab before you return to running.
5. As part of your regular running routine you should include simple plyometric exercises which strengthen all the tissues of the lower limb and encourage energy storage and return.