Carry the Weight: Does Running Ultramarathons Cause Long-Term Foot Damage?
Endurance runners spend a lot of time talking about their feet. Eavesdrop at the starting line of any ultra, and you’re likely to hear the chatter: kindly blister tip exchanges; vigorous debates over shoe style, arch supports, or how and when to use compression socks; endless hand-wringing over plantar fasciitis; and constant anxiety over proper foot strike patterns.
Despite this obsession with maintaining their feet, there seems to be a generally accepted superstition in the running community that the accumulation of wear from years of ultras will eventually saddle the sport’s most dedicated practitioners with chronic, debilitating foot conditions.
So, are the best distance runners truly doomed to painfully shuffling through their twilight years? Let’s look at the evidence.
Recognizing the Immediate Risks
Unfortunately, due to the relative youth of the sport, we don’t yet have a large enough sample size of lifelong endurance runners for any study to reach a definitive conclusion on the long-term effects, but we can to build a case by looking at the common short-term foot injuries that distance runners face.
Setting aside blisters and bunions, the most common foot maladies faced by runners fall into two categories: , and stress fractures. Both categories are the result of repeated microtrauma: in the former, inadequately repaired minor tissue damage in tendons leaves them weakened and vulnerable to more significant re-injury. In the latter, degeneration of bone occurs too rapidly for the body to repair it1.
Another common running injury is plantar fasciitis, a degeneration in the soft tissue that holds up the arch of the foot2.
The first bit of good news here is that none of these conditions is considered chronic or incurable. Tendinopathies do seem to carry a high risk of re-injury, but the risk is mitigated by exercise (to increase the strength of the tendon), making it reasonable to infer that a return to running after such an injury is the safest course5.
You’ve probably also noticed that none of these complications is unique to runners, nor even to athletes. That’s the other good news: running may increase an individual’s risk of developing certain injuries or conditions, but it does not create any risks of its own.
Treatment and Prevention
Photo Credit: Treatment and Prevention Of your foot
Let’s get the obvious out of the way: untreated or improperly treated injuries will cause long-term damage, particularly if placed under continued strain. That’s as much true for the guy on the couch as it is for the woman running the Barkley Marathons. But for the athletes who do seek responsible medical care, the future outlook isn’t nearly so grim.
Treatments for tendinopathies, stress fractures, and plantar fasciitis tend to follow the same basic procedures. Rest, ice, pain relievers, and anti-inflammatories are used to reduce pain and encourage healing until the injured area is adequately repaired to begin a progressive course of exercise. Load is then gradually increased until the foot is restored to full functionality1. Sometimes surgery is employed to accelerate repairs, or else to re-break improperly healed bone in the case of some stress fractures, but this is considered a last resort.
Both during and after recovery, emphasis is placed on correcting the foot posture that caused the pain in the first place. As Dr. Dave Hannaford, a podiatrist who has completed the Badwater 135 and Western States 100, wrote in Ultrarunning Magazine, “In high-mileage ultrarunning the feet have to be pretty close to optimal or pain and injury result. Every day in my practice I am amazed at sometimes how little is required to cure injuries which have been present for years. For many runners, a wedge the thickness of a nickel placed accurately can be enough, shifting the motion closer to optimal.3”
That leads to more good news: the same plantar short foot muscle exercises that are vital components of rehabilitation can (and should) be used by healthy runners to correct their foot posture, both reducing the risk of injury and mechanically improving the ability to run4. This suggests that athletes who have suffered, and responsibly recovered, from foot injuries may be at a reduced risk of future injury due to form improvements made incidentally in the course of their rehabilitation work.
OA? No Way
Photo Credit: Running Ultramarathons Cause Long-Term Foot Damage
Osteoarthritis, commonly called OA or degenerative join disease, may be the number one fear among long-time runners. OA is a complex condition characterized by a breakdown in the tissues that connect joints, and the tendons and ligaments around those joints.
OA has long been a serious concern amongst runners, but multiple studies have shown that habitual running does not increase the risk of developing of the condition, nor the severity in those who have already developed it. One study, published in the Journal of the American Medical Association (JAMA), followed a group of male runners with a mean age of 56, and a second group of male non-runners with a mean age of 60, over a 12-year period. Using radiological examinations supplemented with subject self-reporting, they reached the following conclusions: “Our observations suggest, within the limits of our study, that long-duration, high-mileage running need not be associated with premature degenerative joint disease in the lower extremities6.”
Due to the relative prevalence of knee OA compared to OA in the joints of the foot and ankle, the majority of research on the effects of running on the development of OA focuses on the knee. While the indirect nature of these studies does call for caution (and further study), the results are nevertheless encouraging. One study, conducted with a larger group over nearly two decades out of Stanford University, reached similar conclusions to the JAMA report: “This study was unable to document that long-distance running among older adults confers any deleterious or protective effects on the development of radiographic OA… Long-distance running or other routine vigorous activities should not be discouraged among healthy older adults out of concern for progression of knee OA7.”
No Evidence of Long Term Damage
In what may be the most comprehensive medical research conducted on ultrarunners to date, Dr. Martin D. Hoffman’s Ultrarunners Longitudinal TRAcking (ULTRA) Study, published in 2014, collected self-reported data from 1,212 active ultramarathon runners.
The ULTRA study had a broad range of findings, all of which warrant further study. Among the conclusions, ULTRA appears to show that Ultramarathon runners are more likely to experience asthma and allergies than the general population, and are more likely to experience stress fractures in the foot than shorter distance runners (risk of most other injuries appear to be roughly equal between short and long-distance runners).
Despite these minor risks, the overall conclusions were optimistic. The study notes, “Compared with self-reported data from the general population, the prevalence of virtually all chronic diseases and mental health disorders appeared lower in the ultramarathon runners9.”
Even more interestingly, “the present study found that greater age is associated with a lower injury risk among ultramarathon runners.” This finding reinforces the idea that running maladies are most often caused by form and posture problems, further suggesting that endurance running presents more benefit than risk over the long term.
Hoffman himself supported this conclusion in a 2018 interview with The Irish Times, when he said, “At present, there is no good evidence to prove there are negative long-term health consequences from ultramarathon running.”
That may be a hard answer to swallow. You’d expect that carrying an entire human over thousands of miles per year for decades would eventually wear a foot down to the bone, like the treads on a tire (or on your old running kicks), but recent research may have begun to uncover the explanation.
The Magical Human Foot
A research team followed along with 44 runners at the 2009 Trans Europe Foot Race (TEFR), a 4,487km race from southern Italy to the North Cape in Norway. The subjects were scanned with a Tesla MRI scanner every three to four days over the course of a 64-day period.
During the first 1,500 to 2,500 kilometers, nearly all cartilage in the lower legs and feet of the subjects was observed to have degraded significantly, but what happened next was a surprise:
“Interestingly, further testing indicated that ankle and foot cartilage have the ability to regenerate under ongoing endurance running,” Dr. Schütz explained when presenting the findings to the Radiological Society of North America. “The ability of cartilage to recover in the presence of loading impact has not been previously shown in humans. In general, we found no distance limit in running for the human joint cartilage in the lower extremities.”
We’ve only begun to understand this ability of the human foot to recover while still under extreme duress, but it goes a long way toward explaining why we don’t see significant evidence of damage to the feet of aging endurance runners. As Dr. Schütz remarked in his presentation, “The human foot is made for running.”
- William Micheo, MD, Brenda Castillo, MD, Alexandra Rivera, MD, and Odrick Rosas, MD Ankle and Foot Overuse Disorders. PM&RknowledgeNOW. 09/20/2014. https://now.aapmr.org/ankle-and-foot-overuse-disorders/#references.
- David Geier, MD. Foot Pain: Common Causes in Runners and Joggers. https://www.drdavidgeier.com/common-foot-pain-injuries-runner-jogger/
- Dave Hannaford, DPM. Understanding Your Feet. Ultrarunning Magazine. 11/24/2013. https://ultrarunning.com/features/understanding-your-feet/