Size matters!

Published 1st October 2020 by mymo

Size really does matter when it comes to buying running shoes, and it might take a bit of practice and experimentation to get it right. The size of your trainers is likely to be different to your everyday shoe for a number of reasons including the brand of your shoe, whether you need custom orthotics, how you land, if your feet swell up when they are hot, and general comfort.

You can gain advice from other runners and in online forums about sizing for particular brands, but the best thing is always to try a few different sizes, making sure you are wearing the socks you would usually run in, too.Properly fitted shoes maximise performance, ensure comfort and prevent nasties like blisters, hot spots, burning and lost toe nails.Here are a few popular brands we have tried with some sizing advice.


A runners’ favourite thanks to comfort and price, Saucony is a brand with a dependable history and often recommended on running forums, particularly as a mileage shoe. The popular ISO, Ride and Triumph are often described as a great fit with runners usually only taking half a size up from their usual fit. Saucony’s fabulous new racer Endorphin Pro is reported to be true to size, with a slightly wider toe box that is perfect for the latter stages in your race.


Asics’ huge range of neutral, stability and racing shoes is ever-growing and ever-popular with runners. Their long established range is often described in reviews as slightly narrow in some models, giving runners the requirement of going up at least half a size to ensure comfort when feet become hot over longer distances. Those with narrow feet find them to be spot-on, so give them a go in a few different sizes and make sure you experiment with different sizes if you change models.

New Balance

New Balance shoes including the ever-popular Fresh Foam range have some great variation in the female/male and standard/wide fit meaning you have loads of options to experiment with when looking for the right fit. They aren’t far off being a true fit overall, but it’s good to experiment with going up a half size just to make sure. The new brilliant racing shoe from New Balance Fuel Cell TC promises a great fit that is true to size so expect a light and good-fitting shoe for faster workouts.


Hoka promise to remain true to size, but often have a narrow forefoot that may pack a pinch. We find in the newer models such as Clifton 7, it’s a good idea to go up half a size, or to check the fit of the wider version where available. Recently, during a jaw-dropping record run of 874 miles from Land’s End to John O’Groats in 12 days, 30 minutes and 14 seconds, Carla Molinaro rotated two pairs of Clifton 7: one in her standard size, another in a wide fit pair to allow for her feet swelling up each day.


Nike varies depending on model, and often depending on what you want the shoe to be able to do. Many find the mileage shoes such as Pegasus true to size with a generous but not too wide forefoot, while the racier shoes require experimentation. Nike’s groundbreaking racer Vaporfly 4% was a narrow fit with a true-to-size length that was comfortable and fast, while the Next % and Zoom Fly racers were reported by many to feel slightly longer, requiring runners to take half a size down.


Mizuno is another brand that seems to vary in sizing depending on the model you go for. Their popular Wave Rider, now on version 24, is definitely a go-to shoe for many with a great fit around the forefoot. Most Mizuno runners suggest going up half a size for best comfort, with some also suggesting experimenting with different lacing techniques to get the fit spot on.


All mileage shoes from Brooks come with the guidance that the best fit for most people is to go up half a size to a size bigger than standard shoe size. Brooks’ popular racing shoe, Hyperion seems to follow the same pattern where slightly bigger is better. Like Hoka, Brooks is a shoe with a great range in wide fit trainers so it’s worth also experimenting with the wide fit if you choose to stay in your standard size.


Adidas has often been reported as a narrow fitting shoe, especially in the older racing styles. Most runners choose half a size up in mileage shoes such as the UltraBoost for best fit, but the latest technology in the Adizero Pro racing shoe is reportedly perfectly true to size. Like Nike, models vary in width as well as length and it’s worth trying a variety of sizes on before you commit.

If you want to read more on sizing including how to measure your favourite shoe against another, check out this article on RunningXpert.


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