Early on in this series (Articles #6 and 13) the topics of running shoes and plantar fasciitis were explored separately. The effects of the former and causes of the latter were explained; of course, this was several years ago and while most of what was written still holds true (at least as best as we can tell), the time seems right for an update on these topics.
Plantar fasciitis remains one of the most frequently observed running injuries. In fact, it is probably the most commonly encountered musculoskeletal ailment of the foot in the general population, including sedentary individuals. Conventional wisdom promotes the notion that this malady is the result of some biomechanical fault that, over time (the injury is not usually thought to be a traumatic one), causes increased stress on the band of connective tissue , with eventual failure, inflammation, etc. Most experts point to overpronation (flatfoot) as the prime culprit, with tight calf muscles running a close second.
I generally have no problem with this theoretical model, though observations made over the past several years have caused to me ask some questions. For example, experience tells us that very often sufferers of this injury present with either normal or high-arched feet. Why do they also develop plantar fasciitis? And, since it is so often seen in the non-running population, we have to wonder if the extra stresses associated with running truly play a crucial role in causing the problem. Finally, the question must be asked – Why does this injury occur in people who have never experienced this problem in the past, despite years of training or daily walking, and who have not appreciably changed their training or daily routine just prior to the occurrence of the injury? If the assumption is that these individuals possess essentially the same biomechanics they have always had, why do they acquire this injury now?
I believe the answer to these perplexing contradictions can very frequently be found in the history of the shoes. The key piece of evidence is in how often patients recount that they had purchased a new pair of shoes – running or otherwise – within a few weeks prior to the onset of their pain. And, it doesn’t seem to matter that much whether the shoes are the same or different model. This suspicion is confirmed when, after switching back to their old shoes, the patient”s symptoms quickly diminish.
Most of the time, it is impossible to identify the reason a particular pair of shoes triggers plantar fasciitis. I do believe that the quality control of many shoe companies is less than desirable and that even a minor flaw in the construction of a shoe can result in a change in the biomechanical properties of that shoe. Thus, even a new pair of your favorite brand and model may cause a problem. Certainly, trying a completely different type of shoe brings even greater risks for encountering a change in biomechanical properties significant enough to bring about an injury, and this applies to all running ailments, not just plantar fasciitis.
My advice then, is to replace your shoes before they are completely worn out or compressed, but keep them in your closet. If you begin to experience heel pain within a few weeks of wearing your new shoes, try running in the old pair to see if your symptoms are markedly improved. If so, you should assume that your new shoes are defective or ill-designed for your foot in some way and you will just have to accept that and eat the cost. Remember, those shoes only cost maybe $90; keep wearing them and you’ll be paying far more for treatments that really may not have been even necessary.