Treading lighter while running may avoid foot injuries
Study indicates treading lightly is a good way to protect your feet
Warm weather is on its way across the country and so are spring marathons, meaning that many people soon will begin a new or augmented running program. Many also will wind up sidelined by injury. But a new study suggests that being light on your feet could keep most runners healthy.
Running injuries are extremely common, with some statistics estimating that as many as 90 percent of runners miss training time every year due to injury.
But the underlying cause of many of these injuries remains in question. Past studies and popular opinion have blamed increased mileage, excess body weight, over-striding, modern running shoes, going barefoot, weak hips, diet and rough pavement or trails. But most often, studies have found that the best indicator of a future injury is a past one, which, frankly, is not a helpful conclusion for runners hoping not to get hurt.
So for the new study, which was published in December in The British Journal of Sports Medicine, researchers at Harvard Medical School and other universities decided to look at running injuries, one of the more obvious but surprisingly understudied aspects of running, and to focus their attention, in part, on those rare longtime runners who have never been hurt.
Specifically, they set out to look at pounding, or impact loading, which means the amount of force that we create when we strike the ground. Pounding is, of course, inevitable during a run. But runners with similar body types and running styles can experience wildly different amounts of impact loading, and it hasn’t been clear to what extent these differences directly contribute to inju- ries.
The researchers recruited 249 experienced female recreational runners, who were chosen in part because they all struck the ground with their heels when they ran. Most runners are heel strikers, and heel striking is believed by many running experts to cause higher impacts than landing near the middle or front of the foot, possibly contributing to an increased risk of injuries. (The scientists focused on women so that they would have one less thing to control for in their results.)
The volunteers reported to a biomechanics lab, where they completed questionnaires about their injury history and then strode along a track equipped with force monitors to determine their impact loads.
Afterward, the scientists asked each volunteer to complete an ongoing, online running diary and injury log.
The researchers tracked the runners for two years.
During that time, more than 100 of the runners reported sustaining an injury that was serious enough to require medical attention. Another 40 or so reported minor injuries, while the rest remained uninjured.
More remarkably, in the minds of the researchers, 21 of the runners not only did not become injured during the two-year study but also had not had a prior injury.
Intrigued, the scientists decided to compare that small group’s impact loading with the pounding experienced by the seriously injured runners, because, the researchers theorized, the contrast between these groups should provide the most telling data about whether how hard you land affects your risk of being hurt.
The answer was that it does. The never-injured runners, as a group, landed far more lightly than those who had been seriously hurt, the scientists found.