Plantar Fasciitis in Runners: Why It Happens and How to Keep Training Through It.
With the Cardiff Half Marathon just around the corner on 4th October, training mileage across the city is climbing. Long runs along the Bay, tempo sessions round Roath Park, hill climbs towards Caerphilly Mountain, it all adds up, and for a lot of runners that is exactly when heel pain starts creeping in. Plantar fasciitis is one of the most common injuries we see in clinic during a half marathon build-up, and it can be one of the most frustrating. This is because it rarely stops you dead; it just nags and gets worse the more you ignore it.
What is plantar fasciitis?
The plantar fascia is a thick band of tissue that runs along the sole of your foot, connecting your heel bone to your toes. It supports your arch and acts a bit like a spring, storing and releasing energy with every stride you take. When that tissue is repeatedly overloaded, small amounts of damage build up faster than the body can repair them, and the fascia becomes thickened, irritated and painful, particularly right where it attaches to the heel.
For runners, this is almost always a load management problem. A sudden jump in weekly mileage, a return to speed work too soon, worn-out trainers, or simply asking tired, tight calves and glutes to do more than they are prepared for.
There is also a mechanical piece to this that's worth understanding, because it is often what separates a niggle that clears up quickly from one that keeps coming back. Your plantar fascia is part of what is known as the windlass mechanism, essentially the way your arch tightens and becomes rigid as you push off through your toes. When your foot does not move through the gait cycle the way it should, that mechanism cannot do its job properly, and the fascia ends up taking far more strain than it is designed for.
How your foot is shaped and how it moves both play a part here. Over pronation, where the foot rolls too far inward on landing, can gradually stretch and weaken the fascia over time. This often goes hand-in-hand with weakness in the deep shin muscles that hold your arch up, meaning the fascia has to take on extra work. At the other end of the spectrum, a very high, rigid arch (pes cavus) struggles to spread load evenly across the foot, concentrating stress in smaller areas instead.
However, either way, left unaddressed, tends to produce the same result: persistent strain on the fascia and surrounding tissue.
It is rarely just about the foot.
Because both feet carry your entire bodyweight with every step, problems here do not tend to stay local. Overpronation does not just affect the arch, it can rotate the whole lower limb inward and tilt the pelvis, which may throw off alignment further up through the spine. This is a big part of why we do not just look at the sore spot on your heel, treating the foot in isolation can often miss what could be driving the problem.
What it feels like
A sharp, stabbing, or burning pain that starts on the inner underside of the heel and can spread forward towards the arch.
Pain that is worst during your very first few steps in the morning, or after sitting for a long period.
A gradual build-up of pain throughout a training block, rather than appearing suddenly after a single run.
Tenderness when you press directly along the inner heel or arch.
How chiropractic care can help
Because the foot is just the end of a kinetic chain that runs up through the ankle, knee, hip, and pelvis, restrictions further up can change how load passes through your arch.
Adjustments or mobilisations to the ankle, foot and lower back help restore normal movement through the joints that have become stiff or compensating, taking some of that repetitive strain away from the fascia itself.
We also use shockwave therapy in clinic for plantar fasciitis, and it is one of the most effective tools we have for it. Shockwave works by delivering focused acoustic pulses into the damaged tissue, which stimulates blood flow and kick-starts the body's own repair process in an area that often struggles to heal on its own because of how little blood supply the fascia gets. Research backs this up, shockwave therapy has been shown to produce better long-term results than a lot of more traditional approaches, and pairing it with other treatment such as dry needling tends to improve outcomes even further. For a lot of runners who have been carrying heel pain for months with little improvement, this is often the thing that finally gets things moving in the right direction.
Alongside hands-on treatment and shockwave, we give you a specific loading and stretching programme, and this part matters more than people often expect. Tightness through the calf, especially the upper calf muscle just below the back of the knee, is strongly linked to how much heel pain someone experiences, so calf and Achilles stretching is usually front and centre of what we prescribe. Foam rolling alongside stretching has also been shown to further improve pain and range of movement compared to stretching on its own, so we'll often build that in too. We also work on strengthening that same deep shin muscle, along with the small muscles inside the foot itself.
On top of all this, we look at your training, your mileage, your footwear, your terrain, so we can help you adjust things sensibly rather than just stopping altogether.
Do you have to stop running?
Not necessarily, and for most runners, complete rest is not the answer. Plantar fasciitis generally responds well to a combination of reduced load, addressing the underlying mechanics, and appropriate loading exercises for the fascia and calf. Many runners are able to keep training, just with some short-term adjustments, while treatment addresses the underlying cause.
Training smart for Cardiff Half
If you are building towards the Cardiff Half this October, the best defence against plantar fasciitis is realistic progression, well-fitted footwear, and paying attention to any niggles rather than pushing through them. If heel pain has already crept in, the sooner it is addressed, the sooner you'll be back pounding the pavements with confidence.
If you are a runner in Cardiff dealing with heel pain, or want to get ahead of it before your training ramps up further, come and see us at Proactive Chiropractic & Sports Injury Clinic.