In part one of this article I set the scene that today’s running shoe consumer is all too aware of - the shoe selection scene is one of confusion and products en masse. In my recently released Amazon Running & Jogging Bestseller You CAN Run Pain Free I refer to the running shoe landscape as being a ‘maze’.
Interestingly, very little evidence exists to support the best method of prescribing running shoes to runners. The prescription of shoes based on the three basic foot types was found in 2008 by researchers to not be supported by scientific evidence.[i]
So, if selecting a pair of shoes based on the basic foot type is not supported by evidence, what is a running shoe consumer to base their decision and eventual selection on?
The answer is really quite simple. Follow the following six key considerations when you go to make your next running shoe purchase.
Yes, that’s right – good old comfort. How often have you tried a pair of shoes on, walked a few steps in them, bounced up and down in them and thought to yourself ‘these are comfortable’? If you have, you are well and truly on your way to making a good shoe purchase decision. According to UK sports podiatrist Ian Griffiths, comfort is linked to injury frequency reduction. So go and buy a running shoe based on comfort!
2. Shoe width
Shoe width is important. When you purchased a pair of shoes in the past, the shoe salesperson would bring out the metallic foot-width measuring device. But now, for whatever reason, the width of the foot is no longer measured. Without this measurement, the consumer must rely on the ‘feel’ of the shoe width. At the extremes of shoe width, you do not want your foot to be too loose by selecting a shoe that is too wide in the forefoot (toe box) region. Likewise, you do not want to select a shoe that is too tight, either. Aim for a shoe width that is both ‘snug’ enough in the toe box but still has sufficient room for the foot to swell and move.
Different shoe brands will differ with their width. For example, the width of ASICS will differ from Nike, which will differ again from Brooks. In trying to find what brand is best for your foot, you are best to simply try different shoes from different companies. This will represent a better strategy than being loyal to a particular brand.
3. Stack height
A shoe’s stack height refers to the amount of cushioned shoe material (sole) that exists between the ground and the foot. Two different stack heights are often described: the forefoot stack height and the rear-foot stack height.
(Source: You CAN Run Pain Free!)
A shoe’s stack height is different to its pitch or heel drop (see the following section). Conventional motion control shoes often have a stack height of greater than 30 millimetres, while minimalist type shoes will often have a stack height of 10 millimetres. By having lower stack heights, the minimalist shoes provide for more foot awareness of the road or whatever surface is being run on.
How do you choose a stack height that is best for you? The good news is that there is no hard and fast rule. The bad news is that there is no hard and fast rule! Getting the stack height of your shoes correct comes down to trial and error. I suggest you trial a pair of shoes, taking note of how they make you feel and, of course, any potential niggles that may develop. I would caution you, however, from being too radical in your experimenting. Avoid going from a shoe with a large stack height to a very small one too quickly, because this may result in problems such as unwanted injuries.
4. Pitch or "heel drop"
These two terms are interchangeable – ‘heel drop’ has simply become the popular term for what the footwear industry would typically call shoe ‘pitch’. The terms describe the distance or height between the rear-foot stack height and the forefoot stack height. In other words, they describe the degree of the shoe’s ‘slope’ or the shoe’s gradient.
Historically, the bulk of shoes have had a heel drop of 10 millimetres. Craig Payne, on his blog Run Research Junkie, states that no research, theories, arguments, or rationale exists as to why 10 millimetre has been the standard. He goes on to write that it just appears to be what most runners are comfortable with, with all the major shoe manufacturers designing shoes with a 10-millimetre drop. He also states that he was unable to find any blanket recommendations for the best heel drop for runners.[ii]
With the advent and popularisation of minimalist shoes, the term ‘zero drop’ has become part of the running shoe vocabulary. No research exists to substantiate a zero-drop shoe being superior to a more traditional shoe with a 10-millimetre drop. The rationale from manufacturers of zero-drop shoes is that the shoes facilitate a more ‘natural’ running technique away from a heel strike. The follow-on from this statement is that 10-millimetre drop shoes must facilitate a heel striking running form. Anyone who has observed runners wearing either a zero-drop shoe or a 10-millimetre drop shoe will recognise that it is entirely possible to heel strike in either a conventional shoe or a minimalist shoe, which renders the claims made by some minimalist shoe manufacturers as questionable.
The ideal heel drop is runner-specific. There is no ‘one size fits all’! No conclusive research or scientific review shows either a zero-drop or 10-millimetre drop in a shoe as being superior for either running performance or injury minimisation. As a result, and as with my recommendation for selecting the shoe’s stack height, I suggest you experiment with different heel drop heights. Some runners will do better in a zero-drop shoe, while others will do better in a 10-millimetre drop shoe. Then you can quite simply stick with what ‘feels right’ for you. As Craig Payne cites, there is no systematic ideal height but rather a subject-specific ideal height. To find your individual best heel drop, you must experiment with different shoes.
5. Stiffness in the forefoot
Clinically, I believe that over time all runners should aim to move towards a lighter pair of shoes. However, when selecting a lighter shoe it is important to choose a shoe that has some degree of stiffness in the forefoot. Stiffness in the forefoot appears to be consistent with better performance. Researchers propose that having a stiffer midsole of the shoe can increase the ‘rebound’ your foot gets at the time of toe-off (the final phase of foot push-off). They propose that this increase in rebound can thereby improve a runner’s running economy.[iii] This is evident when you look at racing spikes. They all have rigid plastic that reinforces the forefoot with the aim of reducing the wasted energy for high-speed running at the point of the runner’s toe-off.
Therefore, when you go to a lighter shoe you should still feel the ‘rebound’ from the surface you are running on. The shoe should not be too soft, floppy or thin in the forefoot – otherwise, you will be wasting energy at the time of toe-off.
6. Moving towards lighter weight shoes
While not all runners should aim to go lighter, the obvious benefit to transitioning to a lighter shoe is the likely improvement gain – even if that improvement is very small (such as 1 per cent lessened aerobic load). Elite runners know the benefits of running in lightweight shoes, which is why they race in racing flats – although they will often train in a heavier shoe than they race in.
The key with transitioning to a lighter shoe is to not make the transition too quickly. In order to make a successful transition to a lighter shoe, runners must be prepared to be patient. There will be a transition period to get used to the new running ‘state’, which will differ between all athletes in best method and time course – that is, no set formulas are available to integrate the lighter shoes into a weekly running program.
I suggest making progressive shoe purchases whereby each successive shoe gets lighter over time. For example, it may take you two years to arrive at the pair of shoes that best suits you. In this time, you may transition across two to three pairs of shoes.
However you should go for heavier, more traditional and supportive shoes if you:
- have an existing Achilles tendon or calf injury – if you go to a lighter shoe with a lesser heel height with these types of injuries, you will add additional load to these already sensitive areas and, is most instances, this will aggravate the injury and exacerbate pain
- are comfortable in a heavier shoe and are enjoying pain- and injury-free running
- are able to consistently run with a cadence of 90 single foot steps/min and also exhibit good running technique (covered in You CAN Run Painfree).
[i] Richards, CE, Magin, PJ, Callister, R. op cit
[ii] Payne, C. 2013. ‘What is the ideal “drop” for a running shoe?’. Run Research Junkie. http://www.runresearchjunkie.com/what-is-the-ideal-drop-for-a-running-shoe/. Accessed 20 October 2014.
[iii] Roy, JP, Stefanyshyn, DJ, 2006. ‘Shoe midsole longitudinal bending stiffness and running economy, joint energy, and EMG’. Med. Sci. Sports Exerc. 38 (3), pp: 562–569.
Brad is an experienced and much sought after physiotherapist who owns and runs Pogo Physio on the Gold Coast, Queensland. Brad is also the author of Amazon's best selling ‘You Can Run Pain Free: A Physio’s 5 Step Guide to Enjoying Injury Free and Faster Running’ and regularly contributes to the media (4CRB and Juice 107.3FM Radio, Gold Coast Bulletin, Run for Your Life Magazine).