Rotating two or more pairs of running shoes can produce the following benefits:
(1) reduced risk of injury.
(2) extended lifespan of shoes.
(3) flexibility to use different types of shoes for different types of runs.
It takes up to 48 hours after just a few miles of running for the midsoles of running shoes to fully recover their shock absorption properties. Allowing them time to recover at least that long reduces one's risk of injury and extends the life span of the shoes. In his book, “The Competitive Runner’s Handbook”, Bob Glover says, “Studies show that by alternating two pairs of shoes they’ll last longer than three pairs used consecutively.” He also says, “Rotated shoes retain 80% of their cushioning after sixty runs of an average of 5 miles (300 total miles) compared to only 60% for those not rotated.”