Stiff Running Shoes May Cause Chronic Outer Knee Pain as Compared with Minimalist Running Shoes

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.  

Stiff Running Shoes Linked to Outer Knee Pain
We often associate cushioned standard running shoes with safer running, however accumulating research is showing that there seems to be too many negative, than positive, aspects of certain forms of running shoes. For instance, most cushioned running shoes are inflexible and have a tight, restrictive fit on the natural range of motion of the foot-ankle complex. In this capacity, rotational and torsional forces acting on the knee-joint may be more intensive and damaging as compared with forefoot running in minimalist running shoes (i.e. shoes that are light, flat and flexible and are overall, fairly evenly matched with being barefoot). Bottom line, there really is no real functional reason to wear stiff footwear because their narrow frame not only counters the natural geometry of the human foot, but their stiffness silences the greater engagement of the foot’s muscles and soft tissue groups which may result in poor functional strength.
Minimalist Shoes May Fix Severe Runner's Knee
If you’ve adopted the forefoot running technique to abolish your runners knee pain, but your knees still get sore during running, flexible minimalist running shoes, like the Vibram FiveFingers, may be most effective when it comes to choosing the right running shoe for your knee pain-relief as compared with thickly cushioned, stiff running shoes.

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. 

How Minimalist Running Shoes May Prevent Runners Knee
Forefoot running in minimalist shoes, like the Lems Primal 2, may offer an antidote for knee pain, specifically outer knee pain because for one, you’ll be better connected with the ground which helps reinforce stronger landing stability, including more tight control of overtaxing rearfoot motions. For another, the flexible frame of a minimalist shoe promotes widespread engaging muscular activity throughout the entire foot which enables all sectors of the foot, especially the pronatory muscles, to quickly self-strengthen, and by extension, unwanted heel motions can be more easily controllable as well!

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.

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Bretta Riches

"I believe the forefoot strike is the engine of endurance running..."

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.
Bretta Riches

P.S. Don't forget to check out the Run Forefoot Facebook Page, it's a terrific place to ask questions about forefoot running, barefoot running and injury. I'm always happy to help!

1 Comment

  1. Good to stiffness is not as safe for the knees but knees have never been my issue and I always used to run in minimalist shoes and they served me well. However Ankles became my issue and a stiff running shoe has helped me.
    Anyway you got this article got to the top spot of my google search and answered my question, I was wondering why everyone wouldn’t want stiffer running shoes after the benefit I got from a stiffer pair.

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