So why do we do it? well first off not all shoes are created equal. There are shoes that are primarily designed for running fast or short races in, others that have more cushioning for longer runs, there are trail shoes and track shoes, bassically theres a shoe for every occasion. So unsurprisingly our shoe rack slowly fills with a variety of different shoes.
But there are still plenty of us that have multiple pairs of the same sort of shoe, whats up with that?
The most commonly cited reason is shoe life expectancy. The theory goes that the foam that makes up the mid sole of your shoes slowly degrades or gets compressed over time as the shoe gathers miles. However if you can give the shoe a longer break between usage then the midsole has a chance to relaxe or decompress a little, thus reducing the wear and extending its life. For someone that might run in excess of a shoes recomended life expectancy in a period of 2 months the thought of getting a little extra out of a pair of shoes is quite enticing. There are however dissenters that say that rotation doesnt improve midsole life expectancy, that a shoe wont decompress if you give it some extra time between usage.
There is a second commonly cited theory, that rotating between different pairs of shoes from different manufacturers/lines can help to strengthen your feet because each shoe sits just a little differently and works the muscle group a little differently, that it can reduce your risk of repetitive motion injuries. As with the decompression theory above this also has dissenters, saying that this may infact increase your risk of injury.
Even if you dont believe that, there are still other advantages, if your shoes get wet, dirty or just need to dry out from sweaty feet then having a second pair means you have a nice dry pair ready to put on the next time you want to run, and the wet pair can be left to dry naturally. The drying out properly also helps in avoiding the bacterial bloom that a constantly damp pair of shoes can expect.
Having a newer pair and an older pair allows you to switch between a shoe that is near end of life and one that has most of its life before it. you can recover from the older one in the newer, and the older one will help harden you up a little.
Another great point about having shoes from multiple manufactureres or lines, is that you dont become to strongly attached to a specific shoe, because you can bet the house on the fact that at some point the manufacturer will be making a change to it that you'll not like.
Finally lets also not forget the aesthetic element, what better way to impress those otherwise hard to impress running partners but with a whole plethora of different shoes... perhapes colour co-ordinated with your running clothes...
OK, maybe with that last one im starting to skate on thin ice, but for me at least the evidence seems to point in favour of rotating through several pairs of shoes.
So If your going to start rotating shoes here are some tips to keep in mind.
- Rotate through shoes that have differnt milage on them, stager the shoes and introduce a new pair as the highest millage pair wears out.
- Use the lower millage pair for races and longer runs if appropriate.
- If you find multiple brands that sit well then consider introducing them into your rotation.
- Track the millage on your shoes so you know how long theyve got left, and which shoe you wore for which run.
- Consider purchasing shoes in multiple colours (not only does this increase your fashion quotient, it also makes it easier to track which shoe is which)
Im have a low millage pair of Nike Skylon 11's that are for races upto 10k and for sprint or interval training.
I have a low millage pair of Brooks Ghost 2's that are for longer races.
I have a two pairs of brooks Adrenaline GTS 10's, one with mid miles and one high millage that i only use on my short morning recovery runs now...they are almost ready for retirement now.
I have another pair of GTS 9's that are mid millage that i use in rotation with the mid millage GTS 10's during my regular weekly training.
So its currentl 5 pairs, and Im not really following the guidlines above as im still pretty heavily invested in the brooks GTS line... a carry over from back when i didnt know about shoe rotation.
So what will i be introducing next? probably something lighter and with a lower heel drop. Maybe something from the Saucony line.
BTW, Heres a small selection of online resources i stummbled across while putting this together.
rotating your shoes @ run to win.com
Rotating running shoes @ hillrunner.com
sneaker rotation @ soletheory
shoe rotation @ Ironman 101
two-fers by the shoeguy @ running times
multiple forum threads at runners world.