Explain endurance to me like I’m 5. Or a toddler.

This spring my then 3-year-old son started, to my delight, to take an interest in running. He started wanting to come to the track with me, run around the park by our house and enter local kids’ races. We’re talking 400m to 1km distances, which as adults is within our comfort zones; but for kids, especially toddlers, that’s venturing into middle distance running territory, also known as endurance. I didn’t realize that at first though, it took him complaining of a tummy ache after the first 100-200m’s of every run for me to get it.

At first, I thought we had a fueling issue on our hands; maybe that pre-run pack of gummies wasn’t the right choice; but after a few runs and races, when the same thing kept happening, I realized it was a pacing issue and his tummy troubles were caused by starting way too fast. We found ourselves in coaching territory, something I’m used to talking about with adults; but how do I explain it to a toddler? To my surprise, pretty much the same way I would to anyone else:

Running fast is fun. Wanting to try your best every time you lace up and seeing how fast you can go is awesome, but not every run is a race. If you go slower MOST of the time and learn to pace your runs, it will make running way more enjoyable and allow you to run further and faster in the future.

So, if you’re just starting out and you’re feeling like every run is really hard (or if it’s giving you a tummy ache), take this as your permission and encouragement to slow down. It shouldn’t be that hard all the time, there’s a time and place for that! Building your endurance base is like building the foundations for a house – or a Lego tower; the stronger and more solid that base is, the better it will make your running in the future. Helping you to prevent injuries, get faster and overall make running easier.

It doesn’t have to be that complicated either. For all the people older than 4 that can do some easy runner’s math, here are some numbers I like to live by to build that endurance base:

-  80% of your weekly mileage should be at a pace you could have a full conversation at

-  No more than 20% of your weekly mileage should be fast or hard (that means no hills)

-  Don’t increase your total weekly mileage more than 10-20% week by week

And I promise, if my toddler can master the art of slowing down, so can you! Happy running.

by Steph McGregor - physiotherapist, running coach (@Mile2marathon), most recent PB Chicago (2:57:02).