Does Alternating Running Shoes Prevent Injury?

One of the old adages in running is to rotate through different pairs of shoes for injury prevention.  In other words, have at least two pairs of shoes you can alternate daily.  For some this is natural, with training shoes, racing flats, cross country spikes, performance training shoes, and even barefoot drills part of the normal weekly rotation.  But for others who train in only a single make and model, adding shoes requires foresight (ie. Buying multiple shoes at once or buying your “next” pair long before the current one expires).
One study (Malisoux 2013) put this adage to the test with a group of 264 recreational runners over 22 weeks.  Authors found that “parallel use of more than one pair of running shoes was a protective factor” against running related injuries.   Some possible explanations…

• Shoe engineers would have us believe that allowing each shoe more time between runs gives the shoe material a chance to “recover” and retain its shock absorption properties. 
• Another explanation is that minute differences in each shoe could promote movement variability and counteract repetitive strain forces. 
• Finally, it’s also possible that the runners who invested in multiple shoes also were more invested in other injury prevention measures (massage, nutrition, better training plans) than those who only ran in one shoe. 

Other protective factors included “mean session distance” (how long you normally run) and weekly volume participating in other sports.  The mean session distance is an interesting variable, as it may be counterintuitive that running more may actually promote running health.  Remember that healthy running, to a certain level, simply offers more opportunities to practice the skill of running.  In coaching, we’d call this building positive momentum within your training…the more successful you are now, the more work you can put in to become successful later. 
Finding a connection between non-running sport participation and running health is also an intriguing result.  There are many possible explanations here, but the simplest is that non-linear athletic skills may complement the strict linearity in running that often leads to repetitive strain conditions.
Conclusion
Sometimes old running adages pass scientific muster; sometimes they don’t.  In this instance, the conventional wisdom seems to align with the formal literature, but as with many things, more study is needed to confirm whether a connection exists.  
Reference
Malisoux L, Ramesh J, Mann R, Seil R, Urhausen A, Theisen D.  Can parallel use of different running shoes decrease running-related injury risk?  Scand J Med Sci Sports. 2013 Nov 28. doi: 10.1111/sms.12154. [Epub ahead of print]

(originally published at www.pikeathletics.com)