If the shoe fits: adidas UltraBOOST X trainers are designed for the female foot (£155, adidas.com/ultraboost)
Runners take the world at a pace. Inevitably, paces differ: some people hurtle through 5km, while others pad out 10km. But whatever the speed, the game is fixed — putting one foot in front of the other, for miles — so if the shoe doesn’t fit, that game is thrown altogether.
However, size is a clumsy metric for running shoes. Feet that are the same size can differ in other ways, and that means they’ll need wildly different types of shoe. Furthermore, quirks anywhere in the leg can carry all the way down to the foot: in other words, if you have a crumbling knee, then the shoes you wear will affect how well it carries you.
And last, crucially, trainers are gendered. Not stylistically — footwear is increasingly gender-neutral — but anatomically: men and women need different types of running shoe, as women have narrower heels relative to the width of their forefoot. Feet in the wrong shoes can slide around inside the shoe, affecting stability and speed, and making injury more likely.
We also have “wider hips relative to a knee position and lower leg bone position”, explains Harry Norman, a trainer at Third Space. “This could potentially lead to knee pain on the outside and inward rotation at the ankle, leading to shin pain.”
There is a movement towards female-friendly design. Notably, adidas’s newest shoe, the UltraBOOST X, which the brand says has been designed specifically for the female foot. Adidas designers used motion-tracking technology to analyse the body movements of female runners and calculate where their feet most need support, and where they need space to flex. They used the analysis to craft the shape and functionality of the UltraBOOST X.
What do the specs look like? The shoe’s arch is “adaptive”, which means it gives a little when your foot hits the ground; the knitted upper does the same for the top of the foot and wraps all the way around the bottom of the foot to cushion it and prevent it moving about. The waffle pattern is wider over the toe so the foot is able to breathe. The shoe is so-called for the “boost” midsole that reportedly returns energy to the foot when it hits the ground and provides protection against tarmac (which can set ligaments jangling). Presumably, male runners also require these types of spec but the measurements for the UltraBOOST are all woman.
Adidas hopes the shoe will cater both to casual Saturday runners and competitive racers, but all runners — male and female — must treat shoe selection like an academic exercise.
How do experts approach it? “Whenever I look for a shoe, before trying it on I test to see if the forefoot of the shoe can both flex and create torsion of an outwards rotation at the same time,” says Norman. “If the shoe can move into those positions with my hands then I know the power of my foot can make it do the same. I normally then look for heel support of the Achilles and a toe box wide enough to allow toes to wriggle around freely.”
Work out where you usually train: is it pavements, parks or a combination of both? Running on tarmac requires more cushioning to save your knees. Generally, shoes should be close to the heel but give about a thumb’s-width of slack between your big toe and the end.
Also, consider a gait analysis: many runners roll their ankles inwards when they propel themselves forward — it is called pronation — and flat or high arches can make a difference to how you hit the ground. Previous injuries — especially to the knees or hip flexors — can also affect your gait. Specialist stores such as Runner’s Need or Asics will have a high-spec machine on site; Sweaty Betty has a “footprint test” on its website, which guides you through a less technical version of the same process. Place your foot in water (or paint!) and place it on a piece of paper to determine whether you have high, neutral, low or flat arches; scrutinise your limbs to assess whether you are bow-legged, straight-legged or knock-kneed. It will then recommend a specific trainer.
Finally, if you wear heels, you must consider what you’re climbing into for the run home from work. “Wearing six-inch heels for eight hours in the office, then running home from work in your “barefoot” shoes, will send your lower limbs into overdrive,” says Norman. Pick something with a more gradual slope to ease the impact of the change. Put your best foot forward and you’ll glide through those miles.[“Source-standard”]