Overpronation: measured, and then what?
Pronation is the normal inward roll of the foot after it lands. How much of it someone shows can be measured. What has long been built on top of that, however, stands up to scrutiny rather less well than the confidence of the telling suggests.
What pronation is
After landing the foot rolls inwards, the arch drops a little, and the lower leg rotates inwards with it. That is how it should be: it is the way the foot absorbs the impact and adapts to the ground.
Overpronation means more of that movement than average. Supination, or underpronation, means less. So the categories you hear in a running shop -- neutral, overpronating, underpronating -- are not a sorting into right and wrong. They describe where someone sits on a scale on which almost everybody sits somewhere in the middle.
What the research says
This is where it gets uncomfortable, because the assumption underneath those categories is weaker than the firmness with which it is sold.
In a Danish cohort, the foot posture of nearly a thousand novice runners was measured first. They all received the same neutral shoe, and their injuries were recorded for a year. The runners who pronated were not injured more often than those who landed neutrally; in the group with the most pronounced pronation there were, if anything, slightly fewer.
The second leg the assumption stands on is the shoe advice itself. In large randomised trials among military recruits, shoes were assigned on the shape of the sole of the foot and compared with an assignment that simply ignored foot shape. The number of injuries did not differ.
Together that is an awkward result for advice that has been given for thirty years: measuring foot posture and choosing a shoe type from it yields no demonstrable gain.
What that means and what it does not
Four things that expressly do not follow from the above.
- 1
Not that pronation does not exist
It does, it differs from person to person, and it is visible and measurable. The measurement is not the problem.
- 2
Not that stability shoes are useless
They do not exist for nothing, and anyone who runs comfortably in them has no reason to switch. In practice comfort is the more usable guide than a category.
- 3
Not that complaints are imagined
Anyone in pain belongs with a physiotherapist or a doctor and not on an information page. This measurement does not replace that and says nothing about it.
- 4
But do treat the category with care
If you run without complaints and someone wants to move you to a different shoe type on the strength of your foot posture alone, the basis for that is thinner than the conversation suggests.
What you can look at instead
Of the things that can be changed about a running pattern, a handful have been studied for their effect on running economy: stride length relative to your own preference, how much you move up and down, and how far in front of the hip the foot lands. Those are also the things that sit above the foot.
| What you look at | What you want to see |
|---|---|
| Cadence | around or above 170 steps per minute at easy pace |
| Where the foot lands | close under the body, not far in front of the hip |
| Vertical movement | little up and down; the head stays steady |
| Left-right difference | contact times that are roughly equal |
Looking at your own foot posture
You need no laboratory for this. Have someone film you from behind at an easy pace, with the slow-motion setting on the phone. Freeze the frame just after the foot lands and look at the line from calf to heel: does that heel roll inwards, and how far?
Two things to hold on to. First, everybody pronates, so "it rolls inwards" is not by itself a finding. Second, the foot is precisely the part that is hardest to judge on video: it is small, it moves fast, and the shoe hides half of it.
What happens above the foot -- knee, hip, stride length -- reads considerably more reliably from the same footage. That is exactly why the running gait analysis puts its weight there, and why the page for podiatrists says that foot and ankle remain indicative on two-dimensional video. A measurement that promises more than the footage can carry is not a measurement but an opinion with numbers beside it.
Common questions
- What is overpronation?
- The inward roll of the foot after landing, more pronounced than average. Pronation itself is a normal movement with which the foot absorbs impact; "over" only marks a position on a scale and not a defect.
- Do you need a stability shoe for overpronation?
- That cannot be derived from foot posture. In randomised trials among military recruits, shoes assigned on the shape of the sole were compared with an assignment that ignored foot shape, and no difference appeared. Anyone who runs comfortably in a stability shoe has no reason to switch, and neither does anyone running neutral without complaints.
- Does foot posture predict injuries?
- No. In a cohort of nearly a thousand novice runners, all wearing the same neutral shoe, those who pronated were not injured more often over a year than the rest. On that evidence foot posture is not a usable predictor, and this measurement is not offered as one.
- Can pronation be measured on video?
- Indicatively. The foot is small, moves fast and is half hidden by the shoe, and two-dimensional video underestimates joint angles systematically. What happens above the foot -- cadence, landing point, vertical movement, left-right differences -- is considerably more reliable from the same footage.
Measuring what can be measured
The running gait analysis measures, from an ordinary slow-motion clip, what can be read reliably, and writes the spread beside it. The first analysis is free.
See the running gait analysis