I blogged last month about some preliminary results from a new study comparing the risk of running injury in men and women. Conventional wisdom says that the angles created by wider hips in women put more strain on the knees; the prospective trial I wrote about didn't turn up any sex-related differences in 154 men and women during a 12-week training program, though more analysis of the data is needed.
There's another way you can look at male-female differences in running injuries, though, which I encountered while researching my column in this week's Globe and Mail. You can take a group of runners who are already injured, compare them to a control group of uninjured runners, and see if you detect any within-sex patterns in their biomechanics during a 3-D gait assessment.
That's what Dr. Reed Ferber of the University of Calgary's Running Injury Clinic and his colleagues have been doing. For example, a study published earlier this year in the Scandinavian Journal of Medicine and Science in Sports compared 48 runners with iliotibial band syndrome to 48 healthy controls. As I wrote in the Globe:
Comparing within each sex, the injured female runners displayed greater hip rotation than healthy female runners. The same pattern didn't show up in men, though; instead, injured male runners had greater ankle rotation than healthy males. So while the end result is the same, "females develop this injury from a hip-down perspective while men develop it from a foot-up perspective," Ferber says.
A similar story emerged when Ferber and colleagues at several other universities looked at patellofemoral (i.e. knee) pain. In a study published in Physical Therapy in Sport, they found that injured women had weaker hips than healthy women, but injured men didn't compared to healthy men. Instead, the injured men tended to have weaker knees:
"What this means is that if a runner is injured, they should be receiving a sex-specific analysis to determine the root cause of their injury," Ferber says. "The traditional notion of a 'one-size-fits-all' approach to injury assessment and rehab protocols can no longer be followed."
I found this quite interesting, because we seem to go through cycles where the prevailing message is that weak hips, or weak ankles, or weak core, or weak feet, etc. cause all running injuries. It's obvious that the answer is never going to be as simple as one weakness causing all injuries, but the challenge is figuring which potential weakness applies to which runners – because no one has time to strengthen every possible weak area. The pattern from these two studies hints that hips might be more important for women, versus lower legs for men. Very preliminary, of course, but interesting to consider.
Find your next race.