When I was in undergrad, I was both pursuing a degree in athletic training and playing college lacrosse, which meant I spent a LOT of time in the athletic training room. After graduation I went on to work in sports medicine in the collegiate setting for 4 years. That’s 8+ years of evaluating and rehabbing various lower extremity injuries, both on myself and others. With all that time spent in the sports medicine and performance realm, one thing I realized was hardly addressed was feet. As an athlete, a student athletic trainer, and then a clinician working amongst other professionals, feet were commonly overlooked. It wasn’t until later in my professional career that I truly realized the importance these structures played in our everyday life.
UNDERSTANDING THE FOOT
The foot is a complex structure, with 26 bones, 33 articulations, and over 20 muscles. (7) There are 4 arches that make up the foot, including the medial and lateral longitudinal arches as well as the anterior and posterior transverse metatarsal arches. All these components work together to play a vital role in posture and dynamic movement.
The foot core (which we will discuss in more detail later) can be divided into 3 subsystems: neural, passive, and active. The neural subsystem consists of sensory receptors, the passive subsystem consists of bones and ligaments, and the active subsystem consists of muscles and tendons that attach on the foot. (3, 4)
All three systems interact and work together to accomplish the movement goals of absorption and propulsion (2) That being said, all 3 systems must be functioning properly individually to produce efficient results together. If one system is lacking more stress is placed on another system, and that’s where we begin to see tissue damage and overuse injuries.
The intrinsic foot muscles are of great importance, and directly training them may be the missing link when it comes to treatment protocols. Recent studies have shown that intrinsic foot muscle strength can have direct effects on low limb pathologies, proprioception, and balance. In addition, weakness of these muscles can lead to an increased risk of falls in older individuals due to the role they play in stabilizing the foot and assisting in maintaining balance. (6) There are 4 layers of muscles alone that make up the plantar intrinsic foot muscles, so it’s no wonder they play such a vital role in balance, stability, and gait.
ROLE IN THE KINETIC CHAIN: BASE OF SUPPORT
My favorite analogy when explaining the importance of foot health is “you wouldn’t build a house on a cracked, weak foundation. So why treat our bodies that way”. Our feet are the foundation of our bodies, yet it’s common for them to get overlooked when it comes to training or addressing pain and/or limitations in the lower body. Rather than addressing imbalances, we often push through and try to continue to build on top of pre-existing issues.
Our bodies can be viewed as a kinetic chain; multiple joints and systems connected to function and perform a movement or action. Everything is connected in some way, so when one link is faulty, we tend to see issues further up the chain as a result. Knees and backs are common areas we see overuse injuries in, both in the advanced trainee and the weekend warrior. Unfortunately, weak feet can further progress these injuries (if they weren’t already the root cause to begin with).
When explaining the kinetic chain during an evaluation, my favorite thing to demonstrate is how my posture is affected at each joint when I allow my arch to collapse during weight bearing.
inactive arch or pronating the midfoot > valgus collapse at the knee > internal rotation of femur > anterior pelvic tilt
Some issues you might experience in this position:
- Foot/ankle/low leg: plantar fasciitis, shin splints, stress fracture
- Knee and hip: patellar tendonitis, PFP, ACL tear, ITB syndrome
- Back: low back pain, low back spasms
See how something as small as the muscles in your feet being weak can have a domino effect up the kinetic chain?
Now I’m not saying the lack of strength and coordination in your feet is the sole cause of your back pain or limited knee range of motion, but there’s a good chance it’s playing a pretty big role.
As the saying goes, “you’re only as strong as your weakest link.”
FOOT CORE
In both the clinical and athletic settings, a lot of attention has been given to core strength and stability and the role it plays in lower extremity movement patterns and performance. The musculature that makes up the lumbopelvic-hip complex, AKA the core, has been described as having both local stabilizers and global movers that work together to provide stability and allow proper functioning of the system.(4)
To put it simply, the local stabilizers (smaller musculature that provide support/stability) need to be functioning properly to provide a stable base for the global movers (larger musculature, the primary movers).
Unstable foundation > abnormal/poor movement patterns > ripple effect of overuse injuries up the chain.
In 2014, it was proposed that this same concept described for the core could be extended to the arch of the foot
Just like with the lumbopelvic core:
if the local stabilizers aren’t functioning properly, the foundation is no longer stable, which results in foot-related problems (or other issues moving up the kinetic chains, such as ankle, low leg, and knee problems)
SO HOW CAN WE ADDRESS OUR FOOT HEALTH?
Oftentimes thick-soled shoes, arch supports, and orthotics are prescribed/purchased to reduce or eliminate any pain or discomfort present in feet, ankles, knees, hips, and low back. While these may be helpful temporary fixes, they don’t do much in terms of correcting any underlying issues.
I’d like to note that I’m not completely discrediting the use of these external sources of support, as there is a time and place for everything! They may provide pain relief or reduce additional stress on internal structures while healing – like when someone breaks a bone, they need to be placed in a cast for a period to allow that bone to heal. BUT, prolonging time spent in the cast past the necessary time-frame will only further atrophy the surrounding musculature. The same can be said for prolonged time using/wearing orthotics and thick-soled shoes; the muscles that help form the arch are required to do less due to the external support, causing them to weaken.
Here are some better approaches to improving your foot health:
Spend more time barefoot
Being barefoot increases sensory input received by the bottom of our feet. Sensory input has long been recognized as playing an important role in postural stability and gait patterns. (4) A study conducted in 2009 found that postural stability improved in single leg stance when standing barefoot compared to wearing thin socks. (4) If thin socks can significantly reduce sensory input, imagine what thick soles in our shoes are doing! In 2017, researchers looked at the effects of footwear on dynamic stability during single leg jump landings. Participants performed single leg jumps while barefoot, wearing Vibram 5-Finger shoes, and wearing Nike Pegasus running shoes. They found that as the amount of footwear worn reduced, dynamic postural stability improved. (1) We can conclude from various research studies that barefoot activity helps improve both static and dynamic foot function.
In addition, spending more time barefoot can help you increase motor control of your toes. In traditional shoes your toes are limited in how much they are able to move. This loss in dexterity can negatively impact coordination and stability. Think of the lack of control and dexterity you have when wearing mittens compared to finger gloves; this is the same for wearing restrictive shoewear. We should be able to splay and move our toes just as we do our fingers. Spending more time barefoot can help improve toe dexterity.
Switch to minimalist shoes
A study comparing the effects of wearing minimalist footwear versus conventional footwear over a 6-month period found “daily activity in minimal footwear increases foot strength for healthy adults” (2) Conventional shoes are more rigid in comparison to minimal shoes; this shoe stiffness can weaken foot musculature, as it reduces the demand of muscles during gait. Another study looking to see the effects of minimalist footwear on foot strength found increased strength after just 8 weeks of walking in minimalist footwear 5 times a week; steps began at 2,500k/day at week 1 and progressed to 7,000k/day at week 8. (7)
This isn’t to say you should toss all your shoes right now and buy all new Vivo’s (although we do support that move!). The transition should be gradual, or you could risk injuring yourself. For example, don’t go from running every day in thick supported shoes to trying to knock out 5 miles wearing a pair of minimalist shoes. Start small; begin by wearing them for an hour/day for ADLs and gradually progress into longer periods.
Short Foot Exercise
Recently, the short foot exercise has been viewed as a foundational exercise for foot/ankle rehab; this foundational exercise is like how the “abdominal drawing in maneuver”, aka pelvic tilts, is foundational to lumbopelvic core stability exercise programs. Both exercises emphasize the patient learning to use local stabilizers rather than global movers. (4)
The intrinsic muscles are used to “pull” the first metatarsophalangeal joint towards the calcaneus, causing the medial longitudinal arch to elevate. This should be performed without allowing toes to curl.
You can only get so far when moving and building on a weak foundation. If you’re looking to improve, whether it be for function, health, or aesthetics, I recommend starting from the ground up.
References
- Bowser, B., Rose, W., McGrath, R., Salerno, J., Wallace, J., & Davis, I. (2017). Effect of Footwear on Dynamic Stability during Single-leg. International Journal of Sports Medicine.
- Curtis, R., Willems, C., Paoletti, P., & D’Août, K. (2011). Daily Activity in Minimal Footwear. Scientific Reports .
- McKeon, P., & Fourchet, F. (2015). Freeing the Foot; Integrating the Foot Core System into Rehabilitation for Lower Extremity Injuries . Clinics in Sports Medicine.
- McKeon, P., Hertel, J., Bramble, D., & Davis, I. (2014). The Foot Core System: a New Paradigm for Understanding Intrinsic Foot Muscle Function. British Journal of Sports Medicine.
- Moon, D., & Jung, J. (2021). Effect of Incorporating Short-Foot Exercises in the Balance. Healthcare.
- Ridge, S. T., Mryer, J. W., Olsen, M. T., Jurgensmeier, K., & Johnson, A. W. (2017). Reliability of Doming and Toe Flexion. Journal of Foot and Ankle Research.
- Ridge, S., Olsen, M., Bruening, D., Jurgensmeier, K., Griffin, D., Davis, I., & Johnson, W. (2018). Walking in Minimalist Shoes Is Effective for Strengthening Foot Muscles. The Official Journal of the American College of Sports Medicine.
