Can You Fix Flat Feet? What Changes, and What Does Not

Quick answer: It depends on which kind of flat foot you have, and for most adults “fixing” is the wrong goal. A flexible flat foot — one where an arch appears when you stand on tiptoe or sit down — is extremely common and often causes no trouble at all. Exercise can improve how your foot works, but it barely changes arch height: the best available pooling of arch-strengthening trials found an average improvement of about a quarter of a millimeter. What does respond is comfort, ankle mobility, and how your leg loads above the foot. A rigid flat foot, or an arch that has recently started collapsing in adulthood, is a different matter and should be assessed by a clinician before you start any program.

First: Which Kind of Flat Foot You Have

This is the question that decides everything else, and almost no article about flat feet asks it first. Three quite different situations get the same name.

The flexible-versus-rigid distinction is standard clinical practice: in the flexible type an arch is present when the foot is not bearing weight and disappears when it is, and clinicians confirm it with the Jack test and single- and double-leg toe raises (StatPearls). You can observe the same thing on yourself in about ten seconds.

Two Things You Can Check Right Now

The tiptoe test

Stand barefoot in front of a mirror, feet hip-width apart, and look at the inside of each foot. Then rise onto the balls of your feet. If an arch appears as you rise — and your heel turns slightly inward — you have a flexible flat foot, which is the common and usually benign kind. If the arch stays flat and the heel does not turn in, note that; it is worth telling a clinician.

The knee-straight versus knee-bent ankle check

Stand facing a wall with the toes of one foot a few inches from it. Keeping that heel down and the knee straight, lean your knee toward the wall. Note how far it gets. Now do the same with that knee bent. If you gain noticeably more range with the knee bent, the limitation is more likely in the calf muscle than in the ankle joint itself. This is the logic of the Silfverskiöld test, which clinicians use to separate tightness of the gastrocnemius from a restriction in the joint or the soleus beneath it (Physiopedia).

Both of these are observations, not diagnoses, and neither is a treatment. Their value is that they give you something specific to report: which foot, whether the arch returns, and whether the ankle restriction changes when the knee bends. Those three details will shape what any competent assessment does next.

When to See a Clinician Before Doing Anything Else

One version of flat foot is progressive, and it is the one most often missed. Posterior tibial tendon dysfunction develops gradually, usually in one foot, and the tendon that supports the arch slowly loses the battle. Get it assessed if:

• An arch you used to have is flattening, particularly on one side only.
• Pain or swelling along the inner side of the ankle or foot, worse with activity or standing.
• You cannot rise onto the toes of that foot on its own, or it hurts to try.
• Viewed from behind, more of your toes are visible on one side than the other — the “too many toes” sign.
• The arch never appears, standing or sitting, or the foot feels stiff rather than merely flat.
• Shoes have started wearing down unevenly on one side in a way they did not before.
• You have diabetes, numbness, or reduced sensation in the feet — foot changes need medical attention sooner.

Why the urgency: the deformity is flexible and correctable in the early stages and becomes rigid in the later ones, and early recognition is what keeps the treatment conservative (Physiopedia). This is not a case where waiting to see how it goes is neutral.

The Reassuring Part: Flat Feet Are Common, and Mostly Uneventful

Somewhere between 20% and 37% of people have some degree of flat foot, and it is frequently an incidental finding — noticed during an examination for something else, causing nothing (StatPearls). It also varies by population: one study found 17% among non-Hispanic white participants and 34% among Black participants. A trait that common in people who feel fine is a variation, not a defect.

Children are a separate case, and the news is reassuring: most children do not develop a normal arch until somewhere between ages seven and ten, and most get there on their own.

Arch-strengthening exercise works — just not on the arch

The short-foot exercise is the internet’s standard prescription for rebuilding an arch. A meta-analysis of six trials and 201 people found it produced a statistically significant reduction in navicular drop of 0.23 mm (95% CI −0.45 to −0.02), an improvement of 0.67 points on the Foot Posture Index, and no significant difference in muscle size compared with controls (IJERPH, 2022). Programs ran four to eight weeks.

Read that number again: about a quarter of a millimeter. It is real, it is measurable, and it is not what anyone pictures when they are told they can rebuild their arches. If your goal is a visibly different footprint, the evidence says you will be disappointed.

That is not an argument against doing the work. It is a reminder of what the work is for: how the foot and the leg above it function and feel, rather than the height of a curve.

What Flat Feet Do and Do Not Raise the Risk Of

This is where the research is genuinely useful, and the answer is more specific than either camp usually admits. A systematic review and meta-analysis of 21 studies and 6,228 participants — runners, military personnel, athletes — looked at whether foot posture predicts lower-limb overuse injury (Neal et al., Journal of Foot and Ankle Research, 2014). It found:

• A pronated foot posture slightly increases the risk of medial tibial stress syndrome — shin splints — with strong evidence and a small effect (SMD 0.28, 95% CI 0.14 to 0.42).
• A small increase in patellofemoral pain — pain around the kneecap — on very limited evidence (SMD 0.33, 0.02 to 0.65).
• No association with foot or ankle injury.
• No association with bone stress injuries or with non-specific lower-limb overuse injury generally.
• The authors’ own summary: the relationship “is of small effect.”

Notice what that pattern says. To the extent flat feet matter at all, they appear to matter at the shin and the kneecap — not in the foot. Which is a strange finding if you think of flat feet as a foot problem, and an obvious one if you think of the foot as the bottom of a chain.

When the midfoot rolls inward, the shin bone rotates inward with it — the two are mechanically linked, which is what the animation above shows. Rotate the shin and you change where the kneecap tracks. That is a plausible route from a flat foot to pain two joints higher, and it fits the injuries the meta-analysis actually found rather than the ones people assume.

It also explains why some people get nowhere treating the foot in isolation, and why others find their foot settles once something above it changes. Related: knee pain and conservative care and pronation.

The Most Actionable Thing on This Page: Ankle Stiffness

If your ankle cannot bend upward far enough, your body has to find the range somewhere else as you walk. The nearest available supply is the midfoot, which gets it by rolling inward. So a stiff ankle can produce a foot that collapses more than it needs to — and unlike the shape of your arch, ankle range is something that reliably responds to work.

Restricted upward bending of the ankle is a recognized contributor to flat foot and to heel and arch pain (Physiopedia). The knee-straight versus knee-bent check above is the first step in working out whether the restriction sits in the calf muscle or in the joint, because those need different approaches. We are not going to prescribe either here — which one applies depends on what an assessment finds, and guessing wrong wastes months.

The Orthotics Question

Two true things sit uncomfortably together here, and you deserve both.

The first: orthotics are standard first-line care for foot pain related to flat feet, and in ordinary clinical practice most people with symptoms do acceptably well with them (StatPearls). Plenty of people reading this are more comfortable in theirs, and that experience is real and sufficient reason to keep wearing them.

The second: the research base for adults is still small. A 2021 systematic review found 12 studies covering 170 adults in total. Most measured mechanics, such as plantar pressure, rearfoot motion and joint angles, rather than whether people hurt less or did more, and the authors rated the evidence weak, remarking that “given the weak evidence available, the common prescription of foot orthoses is somewhat surprising” (Journal of Foot and Ankle Research, 2021).

That doesn’t mean throwing your insoles away, and we have no stake in which pair you wear, since we don’t sell or fit them. Orthotics change how load is distributed while you are wearing them. They are support rather than a structural change, and they work well alongside ankle mobility and strength work. If yours help, use them. If you have worn them for a year and nothing has changed, that is a useful signal to look further up the leg.

Flat Feet, Duck Feet and Tibial Torsion Are Not the Same Thing

These three get mixed up constantly, including by people selling solutions for them, and the distinction matters because one of them does not respond to exercise at all.

That third row is the one worth sitting with. If your feet turn out because of external tibial torsion, the rotation is in the bone, so arch exercises won’t change it. What can change is how you load a leg that is built that way, which usually means working on the pattern of strength and mobility through the hip and ankle. That is where the real gains are.

This is also why we ask what someone is actually trying to change before agreeing we can help. Someone who wants their footprint to look different and someone whose shins hurt after every run need different conversations, and only one of them has a realistic target.

Frequently Asked Questions

Can flat feet be corrected in adults?

If by corrected you mean a permanently higher arch, realistically no — pooled trials of arch-strengthening exercise show an average change of roughly 0.23 mm. If you mean becoming comfortable, walking and running without symptoms, and loading the leg better, then frequently yes. The flexible flat foot most adults have is a structural variation, and the useful targets are ankle mobility, strength, and how load travels up the leg rather than the shape of the arch itself.

Are flat feet actually bad for you?

For most people, no. Between 20% and 37% of the population has some degree of flat foot and it is often an incidental finding that causes nothing. The best evidence associates a pronated foot posture with a small increase in the risk of shin splints and kneecap pain, and with no increase in foot or ankle injury at all. If your feet are flat and nothing hurts, there is nothing to treat.

How can I tell if my flat feet are a problem?

Symptoms, not appearance. Specifically: pain or swelling along the inner ankle, an arch that is newly flattening in adulthood or flattening on only one side, inability to rise onto the toes of one foot, or an arch that never appears even when you are sitting or on tiptoe. Any of those deserves a clinical assessment. Flat feet that feel fine do not.

What is the difference between flat feet and fallen arches?

In everyday use they describe the same thing, but the phrase “fallen arches” is more useful when it is literal — an arch that was there and has since dropped. That pattern in an adult, especially in one foot, is most commonly posterior tibial tendon dysfunction, which is progressive and needs prompt assessment. Lifelong flat feet are a different and far more benign situation.

Do I need orthotics for flat feet?

Orthotics are standard first-line care when flat feet cause pain, and many people genuinely feel better in them. The adult research base is weaker than the advice implies — one 2021 systematic review found just 12 studies covering 170 adults, most measuring mechanics rather than symptoms. They redistribute load while you wear them rather than changing your structure. If they help, keep using them; if a year of wearing them has changed nothing, look further up the leg.

How long does it take to see a change with flat feet?

Trials of arch-focused exercise typically run four to eight weeks, long enough to measure small changes in foot alignment but short compared with how long most people have walked the way they do. For symptoms and function, think in months, with steady progress along the way.

Why are flat feet sometimes an issue for military service?

Historically, flat feet were treated as an automatic disqualifier on the assumption that they predicted injury and foot pain under load. Current standards are generally narrower and focus on whether the foot is symptomatic, rigid, or has required treatment, rather than on arch height alone — which is consistent with the evidence that asymptomatic flat feet do not raise foot and ankle injury risk. Specific standards vary by country and by branch and change over time, so check the current requirements for the service you are applying to rather than relying on any article.

Can flat feet cause knee or hip pain?

It is plausible for the knee and the evidence is modest. When the midfoot rolls inward the shin rotates inward with it, which changes how the kneecap tracks, and pooled data link pronated foot posture to a small increase in patellofemoral pain and in shin splints. For the hip the evidence is thinner still. The reasonable position is that the foot is one contributor among several, worth assessing as part of the whole leg rather than treated as the sole cause.

Do flat feet in children need treatment?

Usually not. Most children do not develop a normal arch until somewhere between ages seven and ten, and most arrive there without intervention. A child who has pain, a stiff foot, or an arch that is clearly flattening rather than developing should be seen; a flexible, painless flat foot in a young child generally should not be treated as a problem.

Where to Start

Four situations, and only two of them involve us.

1. Flat feet, nothing hurts, you can do everything you want. Leave them alone. You are one of the twenty to thirty-seven percent, and nothing needs correcting.
2. Anything on the red-flag list. See a physician or podiatrist first. We would tell you the same if you called, and we would decline to begin a program until a progressive tendon problem has been ruled out.
3. Your feet hurt, or your shins or knees do, and you want to understand why. This is where an assessment of the whole leg earns its keep — ankle range, how the shin rotates, what the hip is doing, and how you load in standing and walking.
4. You have done the arch exercises and worn the insoles and nothing has shifted. That is the most informative history of all. It usually means the limiting factor was never the arch.

For the last two, posture therapy is a good fit, and our posture assessment page walks through what we look at so you can judge it before speaking to anyone. What we offer is a structured, progressive program aimed at how your leg loads and how your ankle and hip move, which is what makes feet feel and work better.

If an assessment suggests this is a tendon problem, a bony rotation, or something else outside what we do, we refer out and say so. A free consultation is a conversation, not a commitment, and “this is not for you” is a perfectly normal outcome of one.

Related reading: How to Prevent Bunions: The Posture Connection.

Sources

• Pes Planus — StatPearls, NCBI Bookshelf. Prevalence, flexible versus rigid assessment, adult-acquired causes, and first-line management.
• Neal et al. — Foot posture as a risk factor for lower limb overuse injury: a systematic review and meta-analysis. Journal of Foot and Ankle Research, 2014;7:55. Twenty-one studies, 6,228 participants.
• Effects of the Short-Foot Exercise on Foot Alignment and Muscle Hypertrophy in Flatfoot Individuals: A Meta-Analysis — International Journal of Environmental Research and Public Health, 2022. Six trials, 201 participants.
• Evidence for foot orthoses for adults with flatfoot: a systematic review — Journal of Foot and Ankle Research, 2021. Twelve studies, 170 participants.
• Posterior Tibial Tendon Dysfunction — Physiopedia. Presentation, the too-many-toes sign, single-leg heel raise, and staging.
• Equinus Deformity — Physiopedia. Restricted ankle dorsiflexion, the Silfverskiöld test, and associated foot problems.

This article is for general information and is not a substitute for individual assessment. If an arch is newly flattening, if one foot is affected more than the other, or if you have pain along the inner ankle, see a clinician.