The Shoe Rules Athletics Actually Enforces: 20mm, 40mm, and a Check After You Race

Two numbers, and the events they cover

The sole thickness table is short. Track and field events, excluding track race walking: 20mm. Road running events, and both track and road race walking: 40mm.

Golf regulates its equipment by outcome instead — see the golf ball rollback.

The second line is the odd one. A race walker on a track is allowed the road limit — because race walking is a road discipline that occasionally happens in a stadium, and the rule follows the discipline, not the surface.

Note also that the 20mm limit applies to a spiked or non-spiked shoe alike. The cap is on the sole, not on whether there is metal in it.

Where the sole ends is a matter of definition

You cannot measure “the sole” without deciding where. The regulations decide.

Thickness is taken at the centre point of the shoe at 12% of its internal length — the heel — and at 75% — the forefoot. Two points, both fixed by proportion rather than by anatomy.

The measurement is made on a standard sample: a shoe with a 270mm sole, which is US 8.5, EUR 42, UK 8. And because a size 13 of the same model is inevitably slightly thicker, the regulations say that marginal increase attributable only to size is disregarded.

Then a 5% tolerance applies when a shoe goes to the independent body — 1mm on the 20mm limit, 2mm on the 40mm limit.

That tolerance is not leniency. It is an admission that measuring compressible foam to a millimetre is imprecise, and a rule that pretended otherwise would produce disqualifications that could not be defended.

The jumping-events clause bans a ramp

There is one extra line for jumping events: the sole at the forefoot must not be higher than the sole at the heel.

Under a plain 20mm cap, a jumper’s shoe could sit at 20mm at the toe and 5mm at the heel — a forward ramp, tipping the athlete onto the front of the foot. The clause closes that off. The shoe may be thick, but it may not be shaped to do the work.

Shoe Control happens after you race

The compliance procedure contains an instruction that reads like a lesson learned:

Shoe Control must be conducted after each event the athlete has competed in, and must not be conducted in the call room.

The call room is where athletes sit in the last minutes before competing. Inspecting equipment there means a dispute at the worst possible moment — and gives an official the power to unsettle a competitor minutes before a final.

Moving the check to after the race means the athlete competes, and any consequence is applied to the result rather than to the preparation. It is the same instinct as athletics’ false start rule putting the decision on a machine rather than an ear.

Cross country stopped being regulated

From 1 April 2026, a spiked or non-spiked shoe worn in cross country races can be any thickness. Before that date the road and track limits applied depending on shoe type.

Mountain and trail races were never covered.

The logic is that the shoe regulations exist to protect the comparability of performances — and cross country, mountain and trail results are not compared across courses in the way track times and road times are. Where there is no record to protect, there is nothing for the rule to do.

That is a rare thing in sports governance: a body concluding that part of its own jurisdiction does not need governing. See also how a world record is ratified for what the comparability is protecting.

Prototypes are allowed, but not where it counts

A development shoe — one never sold, being tested by sponsored athletes — can be approved and worn in world ranking competitions for a maximum of 12 months.

But it cannot be worn at the Olympic Games, a World Athletics Series event, or the World Athletics Ultimate Championship.

So manufacturers get real racing data, and the sport’s biggest occasions stay on shoes the public can buy. The prototype is allowed everywhere except where it would matter most.

The four-month rule quietly disappeared

The best-known clause of the original 2020 shoe rules was that a shoe had to be available on the open retail market for four months before it could be raced in. It was the rule that answered the Vaporfly controversy: not “no technology”, but “no technology only you have”.

Under the 2026 regulations that period is gone. An available shoe must be purchasable at any time prior to the start date of the first competition at which the athlete proposes to wear it — and a shoe counts as purchasable through retail, brand websites and apps, and e-commerce, including pre-order periods.

There is also no obligation to restock. If a shoe sold out, an athlete who wanted it can wait or buy something else.

That is a substantial loosening, and it went largely unremarked. A four-month window guaranteed real supply; a pre-order the day before a championship guarantees the form of availability without much of the substance. World Athletics still requires manufacturers to evidence that a shoe was available, so the requirement has not vanished — but it has moved from a duration to a moment.

Spikes, and the ban on shoes that know things

Up to 11 spikes, and no more than 11 spike positions — so a manufacturer cannot offer a shoe with twenty receptacles and let athletes choose.

Projection is capped at 9mm outdoors, rising to 12mm for the high jump and javelin, and 6mm indoors unless the venue permits 9mm. Each spike must fit through a 4mm square gauge for at least the half nearest the tip — a rule about the track surface, not about performance.

And one line worth its own attention: a shoe must not contain any embedded sensing or intelligent technology whatsoever. Athletes may still wear heart-rate or stride sensors personally. The prohibition is on the shoe becoming an instrument.

That is a rule written for a product that mostly does not exist yet — which is the useful kind to write early, as the sport learned when it had to react to the 2010 swimsuit ban after the records had already fallen.