Find Your Perfect Fit: The RUN-CAT Method for Choosing Running Shoes

As athletes know, much more goes into choosing running shoes than colour, shape, trend, style or brand. Whether you're an athlete, regularly participate in casual running events or just want a better shoe to jog in, remember that your running shoe is the main interface between your foot and the ground, and making a good choice will reduce your risk of injury and boost performance.

We used to use the pronation model to fit shoes, meaning we took a biomechanical approach and considered the shape of the arch to fit the shoe accordingly. Evidence from a landmark study using the running comfort assessment tool (RUN-CAT) suggests this approach needs to be revised when comfort and injury prevention are the desired outcomes. We know that a comfortable fit equals a reduced probability of injury, and that comfort and pain relief are far too complex to be reduced solely to biomechanics. So, while a stability shoe can reduce the incidence of pronation-related injuries, it is not effective enough to be considered a good intervention.

Consider your purchase or reconsider your current pair:

Running shoes exist on a spectrum. At the extremes are carbon-plated super shoes and at the other end are shoes with a zero heel drop. I don't recommend using these without prior experience and have been adequately conditioned to run in them.

Use the RUN-cat scale when finding your fit. The Run-cat scale is a principles-based approach to deciding what shoe to buy. This concept uses 5 key questions you should ask yourself when buying new shoes.

1) Heel cushioning: Is the cushioning in the heel too firm or too soft and what does optimal feel like for you? (Your just-right is subjective).

Forefoot cushioning: Under the ball of the foot, is the cushioning too firm, too soft, or just right?

2) The flexibility of the sole: Try rolling off your toes - Do you need more flex in the front of the shoe, or do you need the shoe to be stiffer to drive through the big toe?

3) Shoe Stability: Does it feel like your ankle could roll if you are on uneven ground? (Note: Stable neutral shoes don't need a post, like an insert or motion control. Fewer of these shoes are available as shoemakers shift to producing chunkier styles with more built-up sidewalls, essentially giving you more surface to land on)

4) Overall Support: The upper should not chafe you, and you shouldn't need to break a new shoe in. Your ideal fit should feel as comfortable as wearing socks.

5) Do my toes have enough room? Leave a space the length of your big toe nail between the end of the shoe and the top of your big toe. This guideline ensures enough space to avoid pressure injuries, blistering, toenail damage, and curling of the toes (which is a precursor to a host of other injuries).

With the above principles as a guide, choose a few different brands and feel how the shoe works with your feet. Ideally, run in the shoes on a treadmill or in the road outside the shop. This will give you a feel for all the brands and what results in a shoe that works for you. 

This is a guide for a basic shoe, if you are interested in a carbon shoe or shoes for more specific workouts or distances, the principles change. The idea is to use the research principles to wade through the gimmicks and find something that enhances your running experience.