Roughly 70 per cent of runners will get injured at some point in their life, according to the American Academy of Physical Medicine and Rehabilitation. To address that staggering statistic, hundreds of scientific studies delve into the plight of the sidelined runner. Now, researchers from the Netherlands have combed through the massive body of running-injury literature, hoping to root out patterns to keep runners on the road.
The raw data, compiled from 15 previous longitudinal studies, points to more than a dozen traits likely to sideline runners. The one with the strongest evidence? Runners who’ve already been injured are at a higher risk to suffer the same malady.
“Our findings showed that for both men and women it is very important that when they have been injured before, they should be careful when starting to run again,” the study’s lead author Maarten van der Worp said.
Jordan Metzl, a sports medicine physician based in New York City, sees repeat injuries as a huge problem for recovering runners. “Things like shin splints, Achilles tendinitis, and runner’s knee will heal with time,” he says. “But if you don’t fix your mechanics – the reason the injury happened in the first place – it will come back.”
The paper, published in the online journal PLOS ONE, plucked through 400 studies, ultimately deeming 15 worthy to include in a larger data set. From there, the authors generated common injury traits, separating the results by gender. The list includes men having a higher risk of injury if they are beginners or run more than 65 kilometres a week. In contrast, the results show women are at a higher risk if they’ve run a marathon the previous year, run on concrete, or wear the same pair of running shoes for four to six months.
Take these findings with a grain of salt, though. The wide range of risk factors identified in the research show one thing, according to Dr. Metzl. “Runners are like snowflakes,” he says. “They might look the same from a distance but they are all completely different.”
Van der Worp agreed, saying it’s very difficult to generalise the exact causes of injuries. He does believe, however, in the strong evidence proving one injury is very likely to lead to another unless you change form and mechanics.
For the other traits, Dr. Metzl presents a simple solution. “The biggest cause of running injuries across the board is not enough strength,” he says. “If you want to get back on the road – and stay there – you’re going to have to put in some strength work.”