Why New Barefoot Runners May Sustain Plantar Fascia Injury

When you run barefoot, you also run forefoot, which stretches the plantar fascia, in a good way, to allow maximum elastic energy storage, but this stretching often spurs plantar fascia injury in barefoot running beginners. In shod heel strike running, the plantar fascia stretches to a lesser extent which results in less elastic energy storage, and therefore the natural spring behavior of the plantar fascia is disrupted.

Luckily, because of its scientific backing, barefoot running is gaining recognition as one of the most useful tactics of strengthening the plantar fascia to avoid injury. But, there is another reason plantar fascia injury in barefoot running beginners is caused partly because the plantar fascia is playing a more active role in transferring elastic energy between certain areas of the foot, to allow for better spring during propulsion.

How Barefoot Running Contributes to Plantar Fascia Injury

Why New Barefoot Runners May Sustain Plantar Fascia Injury

When running barefoot, the plantar fascia is essentially fully awake and functions more like spring as compared with running in arch supportive running shoes where the plantar fascia’s spring activity is almost dormant. A new study has found a new role that the plantar fascia plays in barefoot running and that is the plantar fascia was identified as a key energy transfer mechanism between energy absorbing and producing structures of the feet.

  • McDonald et al. 2016 discovered that during the stance phase of barefoot running, the energy absorbed by the metatarsophalangeal joint (MPJ) (which absorbs around 11% of the total mechanical energy of the lower leg) was transferred by the plantar fascia between the MPJ and recoiling medial longitudinal arch (MLA), thereby aiding in positive power generation.

In barefoot running, the plantar fascia seems to be somewhat of a backbone of the spring behavior of the foot. In the same study, the researchers postulated 2 important benefits of the energy transfer mechanism of the plantar fascia during barefoot running:

  1. by providing additional energy to the MPJ and and MLA to aid in forward propulsion with greater efficiency
  2. protects the plantar fascia from strain injury because the power from the plantar fascia that is transferred to the arch is not entirely dependent on passive energy

This action of the plantar fascia was not observed in arch support-shod running, suggesting that running barefoot allows the plantar fascia to act more as an energy transfer mediator as compared with shod running where plantar fasica function is more restricted. This is why making the switch from shod to barefoot running may result in an achy plantar fascia, simply because the plantar fascia is more engaged, as it should be, as a spring/energy absorber mediator.

So, if you are new to barefoot running and suffer from plantar fasciitis, don’t worry, the pain is very temporary and will disappear with more barefoot experience, as soon as this structure adapts.

Be sure to check out more of the health benefits of barefoot running.

Afraid of running barefoot? Here are the running shoes that feel most barefoot-like.

More From Run Forefoot:

Heel Strike vs Forefoot Strike Running

What is a Forefoot Strike

Why Older Runners Should Never Heel Strike

Sore Knee Joints From Running

References:

McDonald et al. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running. PLOS One, 2016;  DOI:10.1371/journal.pone.0152602

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!