Are Your Sneakers the Cause of Your Knee Pain? Science Says ‘Nope’!
With the height of marathon training season around New England about to hit its apex, we thought it may be time to discuss one of the hottest topics we hear in our treatment rooms this time of year; shoe wear.
The million-dollar question every runner wants to know is, how much does a worn-out shoe actually impact your running? In a 2009 study published in the British Journal of Sports Medicine, the answer was “not very much”.
Kong et al tested 24 runners before and after 200 miles of road running in the same pair of shoes. There were a few minor changes: longer stance phase, less forward leaning, and less ankle flexion. However, hip and knee angles were unchanged. Knees are the most common site of two injuries in runners; patellafemoral pain syndrome and ITB syndrome. The deeper the knee bend, the greater the amount of torque that is placed upon it. If the worn out shoes don’t have any impact on how far the knee bends as you run, than worn out shoes are of little concern.
Also of interest in this study was the comparison of different kinds of shoes (i.e. gel, air, spring). The study concluded, “the adaptation strategies to shoe degradation were unaffected by different cushioning technologies.” In other words, all the shoes are pretty much the same.
Although the study provides us with some clarity and insight to the overall speculation of the risk of running in ‘worn out’ shoes, it is still recommended that you monitor the wear of your shoes and consider changing them as they SHOW the obvious signs of wear albeit 20, 200 or 400 miles. The bottom line is that a new pair of shoes is a much cheaper investment than the alternative; an injury.
Our personal recommendation is to train with several pairs of the same shoes and you rotate them around your training in order to have a comfortable, broken in pair of shoes ready for marathon Monday.