Plantar fasciitis is one of the most common issues causing foot pain.
Planatr Fasciitis involves inflammation of the plantar fascia – a tough fibrous band of tissue that runs along the sole of the foot. Often, it is described as a sharp pain under the foot. As if the sole of the foot was “ripping apart”.
The first thing to note in cases of plantar fasciitis is that the inflammation (or symptom) occurs in connective tissue, not muscle. Why is this important in our rehabilitation? Connective tissue exhibits different behaviors than muscles. Because connective tissue comprises thicker, more fibrous, and dehydrated cells, it has a better ability to deform, store energy, and release it all while doing it quickly. This is defined as viscoelasticity. Connective tissue can become compromised when it loses its viscoelasticity. A factor that can compromise it is the rate of loading. This means that if the rate (time constraint) at which the connective tissue is required to deform, store, and release energy exceeds its capacity, it can falter. As the founder of Functional Range Systems, Andreo Spina, would say, if the load exceeds capacity, the result is injury.
A great example showcasing viscoelasticity is something we all played with when we were younger (if you were born in the 90s like I was): Silly Putty. If you slowly spread to the Silly Putty, it will stay together, but as soon as you spread it quicker, it will rip apart. Here, you can see that the rate at which you spread the silly puddy impacted how well it can stay together (its viscoelasticity).
Now, let’s talk about the gait cycle and how it relates to plantar fasciitis. Our centre of gravity shifts depending on which stage of the gait cycle we’re in, and the viscoelasticity of our connective tissue changes accordingly. Here’s a quick summary:
- Heel strike – As we hit the ground with our heel, we have to absorb the force of the ground to slow ourselves down. This requires our tissue to stiffen. The centre of gravity is behind us.
- Mid stance – As we translate our weight over our foot, our tissue needs to deform to begin to absorb force. This requires our tissue to dampen. This is where the translation of our body forward is slowest. The center of gravity is over our foot.
- Push off – As we move forward, our tissues must release the absorbed energy to propel us forward. Translation forward is quickest. The tissues re-stiffen. The centre of gravity is ahead of us.
As you might begin to expect, the issues with plantar fasciitis lie where the behaviour of the plantar fascia (stiffened or dampened) doesn’t match the rate at which we translate forward (rate of loading). People who are predisposed to plantar fasciitis are people whose center of gravity is forward (later stages of mid-stance or push-off) and whose plantar fascia (connective tissue) doesn’t have enough viscoelasticity (ability to absorb the load demand in the required time). In other words, the rate of load exceeds the capacity of the connective tissue because the centre of gravity is forward.
This is why runners (or people who suddenly pick up running) often struggle with plantar fasciitis. If their centre of gravity is forward, their plantar fascia doesn’t have the capacity (or time) to absorb the load that comes with the repetitive nature of running in the short amount of time that the foot is on the ground. Because the translation forward of a runner is quick, the rate of loading on the plantar fascia is very fast, as the time on the ground of the runner is very short.
What does the rehabilitation process for plantar fasciitis look like? The first step would be to bring the centre of gravity backward. Exercises that can encourage the heel strike phase of gait which would feel like “heel heavy” kinds of exercises. An example is slant board goblet squats, which emphasize full inhalation and exhalation. The second step would be to retrain the plantar fascia’s ability to absorb force in a mid-stance-like phase of gait. This would look like any exercise that encourages a slow tibial translation over the foot where the plantar fascia has the opportunity to dampen (deform). An example is the front foot elevated split squat with an emphasis on slow tibial translation.
Addressing plantar fasciitis requires a deep understanding of the unique properties of connective tissue and its role in load management during movement. By focusing on exercises that restore balance to the gait cycle and enhance the viscoelastic capacity of the plantar fascia, rehabilitation can effectively reduce pain and prevent re-injury. Whether you’re a runner, an athlete, or someone dealing with daily foot discomfort, a targeted approach can make all the difference. Consulting a healthcare professional to guide you through a personalized recovery plan ensures not only symptom relief but also long-term resilience for your feet.
About the Author:
Sammy Montiel
Registered Massage Therapist & Fascia Stretch Therapist