This is a common question that we get a lot from runners. When should I change my running shoes? There are many numbers out there bouncing around on the answer to this question. Some say 6 months, some say 2 years. Others say 500km or 1000km.
There is no hard and fast rule when changing your running shoes. It is a very individualised question with a number of factors to take into account.
- What type of shoe you run in – A shoe like a Hoka will wear differently to a shoe like a Nike Free
- What surface you run on – Are you a trail runner, road runner or track runner? All surfaces will shoe different wear patterns on a shoe.
- How much you weigh – This is simple physics. Force (N) = Mass (kg) x Acceleration (m/s
- What your goals are as a runner
The main aim for when you change your running shoes is to move to a new one to prevent injury. There has been some research done on this area. However most of it is not recent (in the last 5 or so years) which does not reflect the gains made in material technology over the past several years in running shoes. With the studies that have been done, there does not seem to be a tidy correlation between an older shoe and an increase in injury. Having said that, these studies were done in controlled lab environments with above average runners. They were not performed in the real world with weekend warriors and social runners.
I hear you saying “that’s all great but just tell me when I need to change my shoes!” Alright alright, here’s my answer. This is with no solid research to hang my hat on and based purely on years of working of runners based on a road running shoe.
Road only female 700-800km
Road only male 500 -700km
Road and trail female 600 – 700km
Road and trail men 500 – 600km
Why the difference between men and women?
This is purely to do with men on the average being heavier than women who will produce more compressive force on the shoe material.
Why different distances on trail?
Even though trail can be softer than road (depending on the weather) the exposure to rock and small stones will can damage the sole and midsole faster.
So what do you do with these numbers?
If you use strava or keep a log of your distances with your phone or smart watch, when you get to the above distances check your shoes. This does not mean you need to go out and buy another pair when you hit the number.
What to check?
Look for bald spots on the tread. If the outsole is worn all the way through to the midsole – Time to Change
Look for warping of the sole. Turn the shoe over and try to line up the heel to the ball of the foot. If you see a bit twist in the shoe – Time to Change
Check inside the heel. Has the material worn away exposing the plastic and you have red marks or maybe a blister on the back of your heel – Time to Change
Feels uncomfortable in any way – Time to Change
If you didn’t change and kept running would you develop any injury?
Probably not. But prevention is the best medicine. If you can reduce any risk of having to stop running, why not do it. Plus you the best part is have permission to get a new pair of running shoes!