A study by Malisoux et al (2013) explored the hypothesis that runners who use more than one pair of shoes in parallel would be at a lower risk of sustaining running related injuries. The study monitored 264 runners over a five month period. The prerequisites were that runners were at least 18 years of age, and running at least once per week.
Malisoux et al (2013) classified runners as single shoe users or multiple shoe users. Multiple shoe users were defined as those who used a minimum of two pairs of shoes, and who alternated them a minimum of two times during twenty two week observation period.
The study found that those who used multiple pairs of shoes were shown to have a 39% lower risk of running related injury than those using only one pair.
Interestingly, multiple shoe users ran in there predominant shoe 58% of the time compared with 91% for single shoe users. I forget that there is a huge percentage of people who only own and use one pair of running shoes. My advice, even without the support of this study is to alternate between at least two pairs of shoes.
33% of the runners studied experienced at least one running related injury during the 5 month period. This is supported by van Gent et al (2007) who concluded that 19-7% of runners have at least one running related injury annually. A running related injury was defined as a physical pain or complaint located in the lower limbs or lower back region, sustained during or as a result of running practice and impeding planned running activity for at least 1 day. This is important to note, as often this statistic is blown out of proportion in terms of percentage and severity.
The study also showed with less statistical significance that involvement in other sports also decreased the risk of running related injury.
There is a need for a larger study with a longer reporting period, though the evidence supports the idea that variation in footwear decreases a runners risk of running related injury.
Malisoux L, Ramesh J, Mann R, Seil R, Urhausen A, & Theisen D (2013). Can parallel use of different running shoes decrease running-related injury risk? Scandinavian journal of medicine & science in sports.
van Gent RN, Siem D, van Middelkoop M, van Os AG, Bierma-Zeinstra SM, Koes BW (2007). Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review. British Journal of Sports Medicine.
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