Types of Foot Nerves That Help Us Run with Less Impact

Yes, the nerves in your feet control your biomechanics, but how? Through barefoot stimulation, which is something that is both under-appreciated and neglected in the running community.

Decades of research on the effects of barefoot running on biomechanics has offered tantalizing insight about how going barefoot spurs immediate corrections in your biomechanics, helping you avoid injury.

Only a few scientists have investigated how barefoot running reduces impact as compared with running in shoes. One of my personal favorites is the work by Robbins and Hanna. For example, their 1987 study found that certain foot nerves are key in the intrinsic absorption of the body during barefoot running, enabling barefoot runners to run with impressively less impact than most shod joggers.

Types of Foot Nerves That Help Us Run with Less Impact

Types of Foot Nerves That Help Us Run with Less Impact

Dr. Steven Robbins MD, one of the first barefoot running advocates, has written extensively on how the nerves in the bottom of the feet help regulate running biomechanics, and when stimulated during barefoot running, these nerves “easily induce avoidance behavior” as compared with running in shoes.

  • According to Robbins, when running barefoot, the noxious sensitive nerves in the feet activate the reflex loop in the spinal cord, helping the barefoot runner strike the ground with a lighter, more careful effort to avoid high impact on the leg.
  • Cushioned running shoes block the sensations on the noxious nerves, interfering with the signal from the feet to the impact-reducing reflex loop of the spinal cord, slowing leg withdrawal and results in a lesser back-kick as well as longer ground contact interaction of the foot with the ground.

The key thing here is that the noxious sensitive nerves need to be exposed to the ground via barefooting for the spinal reflex loop to initiate quick, withdrawal of the leg, to minimize impact on the body at each step. This is how impact avoidance behavior works in the favor of barefoot runners as compared with shod runners. Cushioned running shoes do very little to help diminish impact because they block sensory input at the noxious plantar nerves, and is also why cushioned running shoes are associated with long term consequences in lower leg health.

The reason barefoot running is key in the proper functioning of the noxious sensitive nerves in the sole of the bare feet and the spinal reflex loop is that they rely on mechanical and pressure-sensory stimuli for activation in order to “produce a reliable and pronounced behavioral response involving withdrawal”, says Robbins. Therefore, running barefoot is one of the most effective strategies a runner can do to avoid high plantar loading and overloading to the lower leg.

Because injury rates are so high in runners, scientists are now wondering about the extent of which protective cushioned running shoes help reduce impact. If anything, cushioned running shoes pose a challenge for runners to actually run better because they deter the foot nerves from allowing the brain to construct an accurate perception of the ground. Based on the above information, it would be wise to do some barefoot running before you continue running in your shoes to essentially save your feet from further nerve damage caused by your footwear.

More From Run Forefoot:

Health and performance benefits of barefoot running

How heel strike vs forefoot strike running are mechanical different

What is plantar proprioception and why using it is the only way to fix your forefoot running form

Why all runners should be running forefooted

References:

Robbins et al. Overload protection: avoidance behavior response to heavy plantar surface loading. Med Sci Sport Exer, 1988; 20(1):85-92.

Robbins, S. E and Hanna, A. M. Running related injury prevention through barefoot adaptations. Med Sci Sports Exerc, 1987; 19, 148-165.

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!