Striding Right – 20 years down the road
Two decades ago, in one of the first installments in this series, I considered the question of whether altering one’s running form could improve performance (Article #7). Citing the available research at the time, which indicated that either lengthening or shortening a runner’s stride length results in a 1-2% increase in energy expenditure, I concluded:
“It comes down to this: your body knows what’s best, not only in terms of overtraining and injury as we have seen before, but also with respect to what is most efficient. Listen to it and just run the way it wants to.”
The part of that statement implying that altering one’s gait pattern will have no effect on injury prevention may have been a few years premature; lately, there has been much written, and increasing research conducted, that contradicts this assertion. The most well-known support for changing running form comes from those who advocate barefoot, or minimalist, running. As we saw in a more recent column (Article #101), supporters of this theory contend that barefoot runners land on the mid- or forefoot, rather than the heel, which they believe to be responsible for the bulk of running injuries.
More recently, there seems to be a compromise of sorts by some who, while they believe that avoiding rear foot impact is the key to reducing injury risk, argue that the type of footwear – or lack thereof – is immaterial relative to the goal of landing in the midfoot. Grant Robison, a former Olympic 1500 meter runner, is one of those.
I recently heard Grant speak at Fleet Feet Sports about his own experience with altering his gait pattern to eliminate his many chronic injuries. Now working with a group called Good Form Running (in partnership with New Balance shoes), he outlined the four essential components of optimal running form: posture, mid-foot contact, cadence, and forward lean. The mid-foot strike is the main factor in injury prevention; the other three elements help ensure that this pattern occurs.
After his presentation, Grant was asked by one attendee if there are any good, scientific studies to support these theories. Grant admitted that such evidence is just now starting to be gathered, but that preliminary data is encouraging. In fact, a review of the available literature does confirm that there is not much out there yet. Just this week, however, a new study appeared in the Journal of Orthopedic and Sports Physical Therapy (Dec. 2011) that gives us reason to believe that old runners can learn new tricks, in terms of effectively altering their running form, as well as evidence to support the claim that such changes may reduce the occurrence of injuries.
Cheung and Davis selected three female runners suffering from unilateral patellofemoral (kneecap) pain, aka Runner’s Knee. All three exhibited a rearfoot strike pattern when running. They each underwent an 8-session, 2-week training program utilizing “real-time” audio feedback to modify her running pattern on a treadmill. Ground reaction forces were assessed before and after the training and again 3 month later. Knee pain scores were obtained by self-report. The results showed that all three effectively reduced several measures that indicate rearfoot impact, and all reported improvements in knee pain symptoms and associated functional limitations. Significantly, these changes held up after 3 months, indicating that the runners were able to maintain the changes in gait pattern even without the assistance of biofeedback.
While this study is admittedly not one to be characterized as “high level” (i.e., it had a very small sample without controls and only looked at one type of injury), it does join a growing list of studies that have shown that different elements of running form (e.g., hip rotation) can undergo changes through training. One problem,of course, is that such training seems to involve a certain amount of technology that the average runner does not have access to. (The subjects had transducers under their heel that emitted a sound if they landed on the rearfoot; they “learned” to avoid that sound by landing on the mid-foot. You could try putting a nail through the sole of your shoe to let you know when you land on the heel, but I probably wouldn’t recommend it.)
It is possible, though, that such equipment may not be necessary. Simply increasing step rate (cadence) may be the means by which the end goal of reducing impact forces in the ankle, knee, and hip is achieved [Med. Sci. Sports Exerc.,Vol. 43, No. 2, pp. 296–302, 2011]. Good Form Running suggests a cadence of 180 steps/minute (3 steps/second); the average runner hits 120 steps/minute.
Increasing cadence, while maintaining essentially the same forward speed and energy expenditure, logically means that stride length will decrease, and this is what seems to foster the mid-foot, as opposed to rear-foot, landing pattern. Fairly simple proposition!
Of the three runners in the JOSPT study, only one reported an improvement in 10k running time after the 3 month re-test, which would appear to confirm at least one claim I made 20 years ago. But while I may still be correct in claiming that altering your gait pattern may not improve performance, and while there are still many experts who would still echo the entirety of my original conclusion, more recent evidence indicates that we very well may be looking at a new way of thinking when it comes to such changes helping to prevent or treat injuries.