Thick cushioned running shoes are not a way to get you out of injury because they affect how your foot interacts with the ground, and not in a good way. It turns out that thick, soft underfoot cushioning causes the foot to mistakenly shift into extreme positions (i.e. overpronation) that was found to produce an assortment of damaging stressors as compared with minimalist running shoes.

A 2015 study in the journal, Footwear Science, found that soft underfoot cushioning caused a flurry of mechanical instabilities and impact forces that increased the likelihood of running injuries.
- The researchers found that medially softer underfoot cushioning induced greater rear-foot motions (more foot pronation), maximum vertical loading rate (more impact loads on the leg), a higher force-time integral (greater loading that lasted longer on the foot and leg) as well as longer ground-contact time (foot spent more time on the ground) during running.
The study’s explanation for this is that thick, soft underfoot cushioning causes prolonged compression duration of the cushioning from the foot during the stance phase of running. The more cushioning the foot tries to press through to reach the ground during running, the more unstable the foot becomes. Out of that comes ankle, shin and knee injury from the transfer of the foot over-pronation to excessive rotation of the lower leg.
Another intriguing, and concerning, discovery from the study was the runners did not perceive these mechanical impediments as troubling or painful! The runners were virtually unaware that their landing surface was destabilized and that greater-than-normal impacts was produced.
In contrast, the study found that firmer underfoot cushioning reduced both over-pronation and eversion (outward rotation) velocity of the foot during running, suggesting that the firmer the underfoot-feel, the more likely your foot holds more steady with the ground when running. The benefit of sturdier footsteps with a firmer cushioned underfoot coincides with recent findings showing that barefoot runners run most stable, with optimal pronatory control on harder surfaces, too!



Another major benefit of running barefoot, or running in barefoot-like shoes, is it helps you make progress in other areas, such as developing stronger, more tolerant feet because it gives the feet the opportunity to work independently that they cant do otherwise when they’re locked in conventional athletic footwear.

The Home Message
To help you secure good foot mechanics in shoes, make sure the underfoot-feel is more firm than soft and squishy because a firmer underfoot provides a more natural feel, similar to running barefoot over earth (which is how we actually evolved to run….), not 40-mm squishy foam.
Likewise, injury prevention efforts that target risk factors, such as over-pronation, should avoid the use of soft cushioned footwear because they cause over-pronation. Instead, the focus needs to be on adding barefoot running to your training since its the only way to get the foots pronatory muscles to be active participants for better pronatory control.
In that that regard, here my other articles discussing the many ways that barefoot running produces results that matter for injury prevention and energy efficiency!

References:
Sterzing et al. Segmented midsole hardness in the midfoot to forefoot region of running shoes alters subjective perception and biomechanics during heel-toe running revealing potential to enhance footwear. Footwear Sci, 2015;7(2):63-79.
If you’d like, you can support Run Forefoot and help keep it going by making a donation in any amount of your choosing:

Or, you can support Run Forefoot by shopping at the BEST Barefoot Shoe Brands, and be sure to bookmark these links 🙂
Lonowear: https://lonowear.com/?ref=cedsholh
Saguaro: https://www.saguaro.com/?ref=9bVA8fEkmDvB-I
Vibram FiveFingers: https://www.anrdoezrs.net/click-7600968-11372648
Vivobarefoot: https://amzn.to/3vycQOY
Be Lenka: https://www.tkqlhce.com/click-7600968-13947200
Xero Shoes: https://xeroshoes.com/go/Run_Forefoot
Iguaneye: https://www.iguaneye.com/?ref=8tfXVc92
Soft Star Shoes: https://shrsl.com/3mp1b
Wilding Shoes: https://bit.ly/3lIygQP