Written by Christopher Ioannou, featuring Dr. Emily Splichal

Reading Time: 11 minutes

Table of contents

• Introduction

• Dr. Emily Splichal and Her Work

• The Connection Between the Feet, Core and Glutes

• How to Activate the Glutes

• The Four Types of Flat Feet and How to Correct Them

• When Orthotics Should Be Used

• The Problem with Modern Footwear

• How to Transition to Minimal, Barefoot Style Shoes

• 3 Daily Foot Maintenance (Reset) Techniques

• The Effects of Training on Artificial Surfaces

• Using Surface Variability to Reduce Injury Risk

• Naboso Technology Inner Soles

• Conclusion

The audio version of this podcast:

The video version of this podcast:

In this episode, I speak with Dr. Emily Splichal, a world-renowned podiatrist who has taught her unique approach to human movement, foot function and barefoot science to 20,000 professionals in more than 35 countries.

She is the author of the book Barefoot Strong and the founder of Naboso Technology, which produces insoles. In our discussion, we cover the four types of flat feet and how to fix them. Dr. Splichal describes the connection between the glutes, core and feet, and how getting all three to work together leads to movement proficiency and longevity. We also delve into the scientifically-backed reasons for which training on various surfaces, such as concrete, increases our risk of developing injuries.

All this and more in episode 2!

The Exercising Health team and I thank Dr. Splichal for taking the time to be interviewed by us and for sharing her knowledge with all our viewers.

We highly recommend reading her book, Barefoot Strong – Unlock the Secrets to Movement Longevity, visiting her website and following her on Instagram. You can also find many of her educational videos on her YouTube Channel.

Furthermore, Dr. Splichal has kindly offered our audience 10% off her sensory insoles using our affiliate code EHEALTH10 at the Naboso online shop.

Dr. Splichal explains that one’s glutes are only as strong as one’s core is stable and that, technically, one’s core is only as stable as one’s feet are strong.

However, despite the obvious interconnection between these three parts of the body, there is just not enough discussion around about how to strengthen the relationship between them. Dr. Splichal believes that this will change in the future as people start realizing the importance of the feet as the foundation of human movement.

Poor connections between the three body parts often present in patterns of dysfunction and foot type. For example, a high-arched, stiff foot is often correlated with tightness in the ankles, hips and thoracic spine.

On the other hand, flat and collapsed arches are often correlated with unstable hips and "sleepy glutes," combined with an unstable thoracic spine.

Dr. Splichal points out that the glutes play a significant role in stabilizing the legs during a single leg stance, which is extremely important in human gait biomechanics (running).  

Because the glutes wrap around the pelvis, they serve not only as hip extenders to open up the hip, but also as hip rotators. This ability to rotate the hips and legs means that the position of the feet will be influenced by glute function and vice versa.

To test this out, stand upright with your feet pointed straight. Then, squeeze your glutes hard and notice what happens to your feet. Relax and repeat the action. One should see movement in one’s feet when this happens, which demonstrates the rotational relationship between the feet and glutes.  

Now, with this relationship in mind, we can start to use rotation during movements such as the squat. So, instead of just thinking about moving up and down, we could think of standing up with a rotation. The way Dr. Splichal explains it, is like corkscrewing your feet into the ground in the squat. Adding this rotational component activates the glutes and unlocks additional power.

1. Overpronated Foot (Muscle Weakness)

Cause: This type of foot has an arch at rest, but during weight bearing the arch collapses inwards under one’s bodyweight. The hips will also typically internally rotate and the knees will come together.
The cause of this dysfunction is weakness of the intrinsic foot muscles that help to support the foot arch.

Fix: Foot-strengthening exercises and proprioception training to stimulate and strengthen the muscles that support the arch.

2. Overpronated Foot (Ligament Laxity)

Cause: This is type of foot has an arch at rest, but during weight bearing the arch flattens under the bodyweight. The hips will also typically internally rotate and the knees will come together. The cause of this type of flat foot is due to a loss of tension in the connective tissues in the foot. Laxity in the connective tissue can be hereditary or can be caused by muscle weakness.

Fix: While genetic ligament laxity cannot be changed, foot-strengthening exercises and proprioception training can improve the function of the foot arches.
Orthotics can also be used in cases in which the pain is severe, under the guidance of a podiatrist.

3. Rigid Flat Foot

Cause: Rigid flat foot usually proceeds from a lifelong occurrence of overpronation. Arthritis sets in and locks the foot in a flattened position. Therefore, the rigid flat foot is most common in elderly people.

Fix: This type of flat foot requires the attention of a clinic podiatrist, especially if pain is present.

4. Pancake Foot

Cause: The pancake foot is genetic and presents as a rounded and flat foot. Asian and African populations tend to have a higher prevalence of the pancake foot than other populations.

Fix: This foot will require shoes that can accommodate their extra width. This type of flat foot requires the attention of a clinical podiatrist if pain is present.

Orthotics or over-the-counter arch supports artificially support the arch and should, thus, only be used in highly specific scenarios.

Here is a list of scenarios for which Dr. Splichal would prescribe the use of orthotics:

1. In someone who is diagnosed with flat feet due to ligament laxity and has to stand a lot at work.

2. People who are currently suffering from Achilles tendonitis, plantar fasciitis or any type of severe foot pain.

3. Runners who have uncontrolled over-pronation. However, the orthotic should be used only during running, and the individual should perform foot- and glute-strengthening exercises to address the underlying issue.

4. Persons who have weak arches and are unwilling to strengthen their feet using corrective exercises might have no other option but to rely on orthotics for arch support.

However, there is no clear cut rule on when orthotics should or should not be used.

Dr. Splichal says that she tries to optimize natural foot function by allowing the feet to be mobile, to have good feeling with the ground and to have unrestricted toe space, and to allow good rotation through the foot and ankle.

Unfortunately, due to the way modern shoes are designed, with their trendy and highly "supportive" features, they inhibit these natural characteristics of the feet.

Dr. Emily says that our feet are designed to do a far better job at supporting themselves and the rest of the body than footwear can provide for us. In fact, when we wear traditional footwear, we actually start losing this innate ability and become too dependent on them.

Dr. Splichal suggests that one be cautious when transitioning to minimally supportive footwear, because the feet are not accustomed to the lack of support and flexibility of these barefoot style shoes at first.

The higher impact, vibrational load and freedom of movement that barefoot shoes allow during movement can be too much for one’s feet to handle at first, especially if one has always worn traditional shoes and is seldom barefoot.

Considering that the average person takes around 10,000 steps per day, with an impact load of 1.5x bodyweight on each step, even just walking in barefoot shoes can turn out to be too much for some to handle right out of the gate.

Therefore, one should slowly transition to barefoot shoes by progressively increasing ones activity level in these shoes over time.

Furthermore, she emphasizes the importance of incorporating a specific foot-strengthening program into one’s training regime in combination with wearing minimalist footwear.

Dr. Splichal believes in giving your feet five to 10 minutes of daily TLC using the following three protocols:

1. Wear silicone toe spacers to improve toe splay and stretch the forefoot muscles and ligaments. This can be particularly useful after wearing shoes that are tight and narrow in the front.

2. Release the bottom of the foot by standing on a golf ball or some other round and textured ball. This trigger-point technique helps to increase blood flow to the plantar facia and muscles, flush out lactic acid and stimulate the nervous system to activate the feet. Dr. Splichal’s Naboso ball was designed for this purpose. You can use EHEALTH10 for a 10% discount on the Naboso Ball or any other Naboso product.

3. Rolling the calf area using a foam roller or even a wooden rolling pin. The rolling should be combined with ankle mobility to ensure that the ankle joint has all the range of motion required to accommodate proper foot function. We include tutorials on all these techniques in our Ankle Stability Course.

Every time the foot lands or exerts force on the ground, vibrations are created within that surface and through the foot. This energy transfer between the body and ground enables us to move.

However, every surface responds and vibrates differently to the impact of our bodyweight. Natural surfaces, such as wood, grass, and earthy trails, will vibrate differently to artificial surfaces such as concrete and tarmac.

Typically, natural surfaces are compliant with the impact of the body, so they will absorb a lot of the vibrations, as well as transmit vibrations back into the body.

On the other hand, many artificial surfaces fail to absorb any vibrations. Instead, they react by sending all the forces and vibrations back into the body. Over-time, these excess vibrations that the body has to deal with can overload the system and lead to injuries.

Many gyms try to minimize this risk by installing thick rubber tiles on top of their concrete floors. The problem with this is that the rubber then does not allow sufficient vibration to make its way back up the body to accommodate efficient movement.

Therefore, the floor needs to absorb some of our impact forces, yet still send adequate amounts of vibration back into the body to give the body energy and promote efficient movement.

An effective way to mitigate the risks of injury due to training on hard, uncompliant surfaces is to constantly vary the surfaces one trains on. Here are a few examples of ways in which one can vary one’s training surface:

1. Change the slope or gradient you exercise on. For example, if you generally run on a flat road, find an incline and do hill sprints.

2. Introduce texture to your workouts. Dr. Splichal’s Naboso Exercise Mat is a great tool for this purpose. A pebbled or cobbled surface is another example of texture variation.

3. Change the surface firmness. For example, wood, tarmac, sand, grass and rubber all provide differences in surface firmness.

Disclaimer: With these recommendations in mind, Dr. Splichal cautions runners who want to add surface variability to their training. She suggests that runners first familiarize themselves with the new surface before running for long distances on it. This is because our bodies carefully tune their biomechanics and muscular contractions to the surfaces on which we run. Therefore, if one is not accustomed to a new surface, then the body might respond inappropriately to that surface in the beginning.

Naboso Technology is a company founded by Dr. Splichal that produces exercise mats and flooring, as well as insoles to help enhance sensory input to the nervous system through the feet.

These products stimulate the body's nervous system through their uniquely textured patterns. Dr. Splichal and her team have found that stimulating the body by means of this additional layer of sensory input helps people to improve their body awareness, balance, walking patterns and even recovery from injuries such as ankle sprains and back pain.

Naboso Technology is currently being tested in various studies to see how it can help people with neuropathy and stroke victims, as well as the elderly population, who are prone to falls. The basic premise is that the enhanced sensation these soles provide can drive neural plasticity in these populations, which can be extremely helpful for their conditions and overall physical well-being.

Dr. Splichal says that her goal with Naboso is to change the way people and the industry view insoles. So, instead of thinking artificial arch support and cushioning, she wants people to think sensory stimulation and enhanced feeling.

I have been personally testing the Naboso insoles for a while now and I've grown accustomed to and really enjoy the extra texture and sensation that these insoles provide when walking, running or exercising.

To me, it feels like these soles bring the outdoors into my shoes, which is really cool. For this reason, I see their value as a permanent accessory to my barefoot footwear.

Dr. Splichal has provided all our readers with a 10% discount on all Naboso Technology products using our affiliate code EHEALTH10 on checkout via their online store.

Well, that concludes the summary of the interview with Dr. Emily Splichal.

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