The evidence is overwhelming that running with a forefoot strike may immediately reduce high stress and impact-loading off the knee-joint which is why forefoot running scores a lot of high points with respects to runner’s knee prevention as compared with heel strike running. However, if you are a forefoot runner who’s still grappling with runners knee, I dug into the research and found that running shoe stiffness may be a serious threat to the knee-joint, specifically resulting in chronic outer knee pain.
For instance, a 2015 study published in the Scandinavian Journal of Medicine & Science in Sports found that running shoe stiffness in the longitudinal direction, but especially at the heel, significantly increased torsional stiffness on the foot-ankle complex which in turn increased rapid rearfoot (heel) motions during the stance phase of running.
The researchers also highlighted in great detail that this type of rearfoot movement commotion in response to stiff shoe materials may profoundly alter the kinematic chain of the lower leg during running. This means each step could become mechanically-threatening and the problem may compound itself more quickly with increases in running speed or volume and may project an assortment of stressors on the leg that may wear down the knee-joint over time.
Another injurious complexity that may lurk from the straining movement patterns of the heel imposed by shoe stiffness during running is that the ankles may now have to wrestle more with continuously reinforcing footstep stability of which this taxing effect may ripple up the leg and may increase mechanical strain on the IT band. This is another risk factor on record for causing outer knee pain during running.
Similar findings were also made in a 1991 study in the journal, Medicine & Science in Sports & Exercise which found that stiff soles forced the feet into extreme positions (rapid eversion and inversion of the foot) which led to increases in ankle instability of which can also be a very difficult undertaking for the knee-joint during running. The researchers also speculated that fast motor actions of the ankle in response to faster eversion or inversion of the foot, may increase mechanical work and over-strain on the IT band, creating a hotbed for outer knee pain to take hold during running.
The Take Home Message
This kind of evidence really helps to validate that footwear plays an enormous role in affecting the way the foot interacts with the ground such that pronation responses (heel motions) may drastically change with shoe stiffness during running. Not only that, this line of evidence is clear that some running shoes, not all, but specifically overly stiff ones, may be an imperfect solution to runners knee pain, since they may keep foot-ground interactions on a harmful trajectory.
What’s very exciting is that because of their ergonomic fit and fluid flexibility essential for good ground adaptation, minimalist running shoes may do a better job at suspending irregular movement patterns of the heel and may therefore help ease mechanical distress off the ankles, knees and IT band during running.
This is why there’s a big positive difference, especially at the anecdotal level, that minimalist shoes can make in potentially protecting and improving your biomechanics and may ultimately take a big role in offering wide-ranging clinical benefits as compared with more traditional fitness footwear loaded with rigid and restrictive stability components.
If you’re interested in learning more about the health and performance benefits of minimalist footwear as well as the types of minimalist shoes that are functionally ideal for helping you uphold the proper forefoot running technique when you need to the most, you can do so here!
Grau et al. Hip abductor weakness is not the cause of ITBS. Int J Sports Med, 2008; 29(7):579-583.
Phinyomark et al.Gender differences in gait kinematics in runners with ITBS. Scand J Med Sci Sport Exer, 2015;DOI: 10.1111/sms.12394
Stacoff et al. The effects of shoes on the torsion and rearfoot motion in running.Med Sci Sports Exerc, 1991; 23(4):482-490.
If you’d like, you can support Run Forefoot and help keep it going strong by making a donation in any amount of your choosing: https://www.paypal.me/RunForefoot
BSc Neurobiology; MSc Biomechanics candidate, ultra minimalist runner & founder of RunForefoot. I was a heel striker, always injured. I was inspired by the great Tirunesh Dibaba to try forefoot running. Now, I'm injury free. This is why I launched Run Forefoot, to advocate the health & performance benefits of forefoot running and to raise awareness on the dangers of heel striking, because the world needs to know.