New Study Tries to ID What Leads to Running Injuries

Running injuries are by far the most common type of injury among triathletes. The average incidence—ie. the number of runners experiencing injury over the course of a year—has been reported as anywhere between 19-79%, with the vast majority related to overuse. Most of these occur in the lower extremities, with the knee accounting for 7.2-50% of injuries reported.

For years, researchers have tried to better understand what leads to running injuries, so as to better inform training and decrease the likelihood of getting hurt. Unfortunately, to date, much of what is known on this subject is either unclear or inconsistent.

For example, there is conflicting evidence on how much shoe cushioning is good or bad, how much running volume or running surface play a role, and whether or not a runner’s physical characteristics like age, sex, or body type are important.

Because of this, researchers continue to perform studies in the hopes of finding better answers. One such group of researchers, out of the Mayo Clinic in Jacksonville, Florida, recently published a paper in the Clinical Journal of Sports Medicine in which they published the findings of a three-year review of participants in the Donna Breast Cancer marathon and half-marathon in order to assess factors associated with injuries among those runners. From 2010 to 2012, they surveyed 1,043 half-marathon participants and 624 full marathoners in order to quantify who they were (age, sex, body mass index (BMI), etc.), as well as what they did for preparation for their race (how much they trained, did they use a plan or a coach, etc.). This information was then compared to whether or not they reported sustaining an injury during training or, after the fact, reported an injury during the event. Additional information collected included athlete’s finishing time and use of non-steroidal anti-inflammatory medications (NSAIDs) during training, among other things.

Are women more likely to get running injuries than men?

So what did this study find? Among the half-marathoner set, 80% were women and 38% reported an injury within the year before the race. Among the marathon runners, 65% were women and 46% reported an injury in the year before the event. Injuries were seen more commonly amongst women, younger runners, and those who reported regular use of NSAIDs. The use of NSAIDs was thought to be a marker of chronic injury more than it was felt to be an actual cause of injury.

Dr. Sara Filmalter was one of the study authors. “We couldn’t explain why women were injured more often than men and we thought that it might have been a product of the sheer volume of women participants in this race,” she said. “For this marathon the population of patients tends to be a little bit undertrained if anything, in part because it is a charity race made up of a lot of women who get excited to go out and support their friend or their mom.” Because of the unique make-up of the race, they didn’t want to conclude that female runners are necessarily more likely to get injured than men, only that this is what they observed in this particular population.

Factors that may cause running injuries

Runners who reported an injury in the previous year, especially to the hip, knee, ankle, or foot, were much more likely to experience a race related injury (24% in the half-marathon group, 30% in the marathon group).

Those runners who followed a plan or who had a coach guiding their training were less likely to sustain an injury in training or racing, as were those who had more running experience. “We believe that following a training plan (or having a coach) led runners to follow a more regimented running program and that reduced the likelihood of running-related injuries,” Filmalter said, “but this was true only for the half-marathon participants. We speculated that among the marathon runners they likely had more experience and didn’t benefit as much from a training plan.”

A couple of the findings were unexpected, as they run counter to the findings of other similar research and are worth noting.

Despite previous studies suggesting that higher BMI may actually have a protective effect on running-related injuries, in this study BMI seemed to be associated with injuries, at least in the full marathon participants. “We wonder if BMI only matters once athletes reach a certain volume or distance or even running pace, but we didn’t look in detail at these factors to be able to say with any degree of certainty,” Filmalter said.

Another interesting finding of the study related to running volume. Unlike previous studies that have suggested increased running volume is associated with a higher risk of running-related injuries, this study found that higher volumes were in fact protective. “Fortune favors the prepared,” was how Dr. Filmalter put it to me. “What our study showed is that you need to be prepared for your race and that the closer you get to race volume either in weekly volume or by having your long run be close to your race distance then this is protective against developing injuries during the race.”

Taking the findings of the study in total, Dr. Filmalter was pretty specific with her recommendations for runners who want to do their best to avoid injury: “Prepare, prepare, prepare, train, train, train,” she said. “Marathon runners tend to be more regimented and diligent with their preparation and this keeps them from getting injured, where half-marathon runners often try to get by on much less training and this can cause them problems.”

So the take home here is that, in fact, running more can be a good thing if it better prepares you for the rigors of a long race. Run more, run healthy.