One common question among runners is when to replace your shoes, with the popular advice ranging anywhere from 300 to 600 miles (482 to 966 kilometers). The justification for doing so is not that the shoe are worn through, but rather:
Don't use the treads of your running shoes to determine whether you should replace your shoes. The midsole, which provides the cushioning and stability, usually breaks down before the bottom shows major signs of wear. If you've been feeling muscle fatigue, shin splints, or some pain in your joints -- especially your knees -- you may be wearing running shoes that no longer have adequate cushioning.
Which means that a lot of runners will replace shoes that look to be in fairly good condition in hopes of avoiding injuries.
In a 2008 research paper for the British Journal of Sports Medicine, Dr. Craig Richards, a researcher at the University of Newcastle in Austria, revealed that there are no evidence-based studies - not one - that demonstrate that running shoes make you less prone to injury.
Where injury is generally defined as conditions such as Plantar Fasciitis as opposed to minor cuts and scrapes to the foot due to the running surface or hazards on it.
Is this claim accurate? Is there no evidence that running shoes prevent injury?