Are Barefoot Shoes Good for Your Achilles? YES!

One of the strongest conclusions from  studies on running footwear (references below article) is barefoot shoes aren’t just excellent for your feet by making them work independently, getting them functionally strong enough to stand up to tougher training, but the flat sole of a barefoot shoe functionally improves the elastic properties of the Achilles, making the tendon significantly better at storing more elastic energy.

Are Barefoot Shoes Good for Your Achilles? YES!
The ergonomic benefits of a barefoot shoe is the sole’s flatness, which specifically lacks thick padding under the heel, makes it easier to leverage a forefoot strike (landing on the balls of the foot) which is the only method to prevent harmful impacts from rising to injury-predisposing levels. At the same time, the lack of under-heel padding permits the Achilles to be better at storing elastic energy that accounts for reduced muscle effort.


Equally beneficial, the sole of a barefoot shoe is also very thin, giving you an enhanced sense of your landing surface whereby increases in ground-feel triggers internal reflexive mechanics that produce a forefoot strike landing, which involves initial ground-contact on the balls of the foot, followed by the heel lowering down to the ground, shown below:

Are Zero Drop Running Shoes Good?
A barefoot shoe makes it easier to detect where you’re landing on your foot, allowing to you keep better focus on your forefoot strike. A proper forefoot strike landing involves lowering of the heel to the ground, which is made fully possible in a barefoot shoe since the sole has no padding under the heel. It’s the heel-lowering phase that enhances the flow of elastic energy in the Achilles, but in a cushioned running shoe (shown below), the elevated padded heel prevents this phase from occurring, thereby limiting vital elastic energy storage in the tendon.
Why Barefoot Shoes Are Better for the Achilles than Traditional Ones
Unlike the heel-lowering phase allowable by a heelless barefoot shoe seen in (B), a standard running shoe, seen in (A), always has more padding wedged under the heel than the front of the shoe. This under-heel padding is a mechanical interference that prevents the heel from dropping all the way down to the ground, which in turn, prevents the Achilles from properly elongating which decreases spring energy return.

The Achilles is more effective in producing more elastic power in a heelless barefoot shoe because it fully allows the tendon to elongate during stance, which was found to allow more energy to be stored inside the tendon, making the tendon more spring-enabled which in turn reduced energy costs for the support and propulsive phase of running (Willwacher et al., 2013). Therefore, the longer the Achilles tendon, the greater the running efficiency (Biewener, 1998; Rubenson et al. 2011).

Black Friday at FitnessFactory.com!

Is It Bad to Run in Cushioned Shoes?
Under-heel cushioning is a big barrier between the heel and the ground because it stops the heel from fully lowering to the ground, which makes it very difficult for the Achilles to elongate in order to recover elastic energy needed to reduce muscle energy costs. The more spring-enabled your running stride is, via allowing the Achilles to elongate during stance, the less muscular effort and energy is needed to push the body forward up and through each step.

As mentioned above, running in shoes with excessive cushioning under the heel limits the amount of ankle-joint moments needed to slacken (i.e. elongate) the Achilles, which reduces the tendons energy-saving elastic power. This is why there are very few physical benefits to these kinds of shoes, but the physical benefits to barefoot shoes are endless because they also increase working conditions in the extrinsic muscles of the foot, thereby improving a runner’s ability to retain exceptional foot strength.

    • According to Willwacher et al. 2013, strong feet work optimally regardless of intense running conditions, and are better able to modify stiffness behaviour. Plus, it makes sense to have stronger feet than not since the stronger your feet, the more adaptive they are to take on harder training!

Take Home Message

In running, footwear fundamentally effects everything from foot strike to foot strength to even the function of the Achilles tendon whereby the smaller the under-heel cushioning of a running shoe, the better the running economy since a shorter heel requires greater elongation of the Achilles during stance, which in turn, enables more elastic energy to be conserved inside the tendon with greater ease, Scholz et al (2008) and Willwacher et al. (2013)

In that light, here are more evidence-backed reasons barefoot running shoes will help improve ALL aspects of your mechanics, from your stride length to better upper body posture to more controlled footstep stability!

If you’ve enjoyed my blog post, you’ll love the content over at my YouTube channel, here, where I show what a proper forefoot strike looks like, as well as why forefoot running is better than heel strike running by every measure!


References:

Biewener AA. Muscle-tendon stresses and elastic energy storage during locomotion in the horse. Comp Biochem Physiol B Biochem Mol Biol. 1998;120(1):73–87.

Rubenson J, Lloyd DG, Heliams DB, Besier TF, Fournier PA. Adaptations for economical bipedal running: the effect of limb structure on three-dimensional joint mechanics. J R
Soc Interface. 2011;8(58):740–755.

Scholz MN, Bobbert MF, van Soest AJ, Clark JR, van Heerden J. Running biomechanics: shorter heels, better economy. J Exp Biol. 2008;211(Pt 20):3266–3271.

Willwacher et al. Does specific footwear facilitate energy storage and return in the MTP joint in running? J Appl Biomech, 2013; 26, 583-592.

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!