The running stride, phase by phase

Running triples the force and halves the time available to deal with it. A treated clubfoot handles three of the four phases much as any foot does, and the fourth is where nearly all of the difference lives.

Written by Heath, who has lived it: casts from birth, a fusion at sixteen, the US Army, and distance running.

One stride

Move through the four phases

Each phase asks something different of the foot. Knowing which one your symptoms sit in is a useful place to start.

Contact, where the foot meets the ground

A cavus, varus foot tends to make contact toward its outer border, because that is where the weight-bearing surface has been tilted. The contact area is smaller than a typical foot’s and the foot is less able to spread out underneath the load.

This is where people become preoccupied with footstrike, often unhelpfully. Where your foot lands is largely a consequence of your structure and your speed, and deliberately changing it can move load rather than reduce it.

Why the outer border takes the contact → What a shoe can do about it →

Absorption, taking the force

In a typical foot the arch flattens slightly, the midfoot unlocks, and the whole structure acts as a spring that stores some of the landing energy. A stiff, high-arched foot does much less of this, so more of the force passes straight through.

What passes through has to be absorbed by the knee and hip instead, which is one reason a runner with clubfoot (CTEV) can have knee symptoms and a foot that seems unremarkable. It is also why surfaces matter more here than they do for most people.

When the knee is paying for the foot → Which structures take up the slack →

Midstance (traveling over the foot)

The body has to pass forward over a planted foot, and running asks for considerably more upward ankle movement than walking does. If the ankle cannot supply it, the movement gets borrowed: from the midfoot, which rolls, or from an early heel lift.

This is the phase behind a complaint that comes up again and again on these pages: a foot that is entirely fine walking and distinctly not fine running. The demand simply crosses your ceiling somewhere between the two speeds.

The restriction, at running speed → Measuring what you actually have →

Push-off, where the difference lives

The last phase is propulsion, and it is the one that is genuinely different. It needs a strong calf contracting through a mobile ankle and a stable forefoot, and a treated clubfoot is usually short on the first two.

Much of the measurable asymmetry in a clubfoot runner can be traced back here. Less force, applied for less time, through a shorter range, repeated every stride for the length of the run.

Push-off in detail → The calf under running load →

Why walking feels fine and running does not

Demand	Walking	Running
Peak force	Lower	Much higher
Ankle movement needed	Less	More
Ground contact time	Long, unhurried	A fraction of a second
Both feet off the ground	Never	Every stride
Energy return expected	Little	Substantial

Every row asks for more of exactly what a treated clubfoot has least of: range, spring, and propulsion. That goes a long way to explaining the gap between how your feet feel at walking pace and how they feel at mile four.

Nothing new goes wrong when you run. The same limits are simply asked for harder.

The one adjustment usually worth making

Cadence. Taking shorter, quicker steps reduces the force in each one and shortens the time the foot spends on the ground, which suits a foot that is poor at storing and returning energy and poor at tolerating peak load.

A modest increase is the usual advice. In the study most often cited, runners who raised their step rate by five percent at the same speed absorbed less energy at the knee, and at ten percent the hip absorbed less as well.8 Those were runners without clubfoot, so treat it as a reason to try it rather than a promise. It is also a gentler change than rebuilding your footstrike, because it adjusts the dose and not the pattern.

Worth adjusting

Cadence, modestly
Surface, where you have the choice
Shoes, which change more than technique does
Recovery spacing between runs
Calf and hip strength, off the run

Rarely worth it

Deliberately changing footstrike
Chasing a symmetrical stride
Minimalist shoes with a stiff ankle
Running through post-run pain that lasts days
Gait analysis against a normal template

That last item deserves a word. Gait analysis can be genuinely useful if whoever reads it understands clubfoot. Analysis that scores you against a standard template will hand you a list of “faults” that are actually your anatomy, and trying to correct them can do more harm than good.

Running mechanics

Does a clubfoot land differently?

Often yes. A cavus, varus foot tends to contact toward the outer border, and a stiffer foot spreads landing force over a smaller area and a shorter time, which sends more of it up the leg.

Should I change my footstrike?

Rarely worth deliberately doing. Footstrike is largely a consequence of your structure and speed, and forcing a change usually relocates load instead of reducing it. Cadence is a safer variable to adjust.

Does increasing cadence help?

It can. Shorter, quicker steps reduce loading at the knee in runners generally and shorten ground contact, which suits a foot that is poor at absorbing and returning energy. A modest increase is usually enough.

Can gait analysis help?

It can, if the person reading it understands clubfoot. Analysis that measures you against a normal template will list your structure as a series of faults, which is not useful and can be actively misleading.

How is running different from walking with clubfoot?

Force rises steeply, both feet leave the ground, and the time available to absorb and return energy shrinks. Everything a treated foot does differently at walking pace it does more of, faster, with less margin.

Which phase of the stride is affected most?

Push-off, most likely. A smaller calf and a stiffer hindfoot both limit propulsion, and that phase is where most of the measurable difference between sides appears.

Why does my foot feel fine walking and awful running?

Because running asks for more upward ankle movement than walking does, plus a spring-and-return the foot may not provide. Restriction that is invisible at walking pace becomes limiting at running pace.

Sources

Where this comes from

1 Clubfoot overview and treatment contextAAOS OrthoInfo 2 Functional evaluation of the treated clubfootPubMed Central 3 Long-term follow-up of surgically treated clubfootPubMed Central 4 The adult sequelae of treated congenital clubfootPubMed 5 Arthrodesis of the foot or ankle in adult patients with congenital clubfootPubMed Central 6 Long-term results of comprehensive clubfoot release versus Ponseti treatmentPubMed Central 7 Three-dimensional alignment and adult residual deformity after Ponseti treatmentPubMed Central 8 Effects of step rate manipulation on joint mechanics during runningHeiderscheit et al. Medicine & Science in Sports & Exercise, 2011

Into a phase

Push-off →The phase where nearly all the difference lives. Midstance and range →Why the ankle limit shows up here first. Asymmetry →What the watch is measuring, and whether it matters.