There are many differences between the best running shoes and athletic shoes, but the one that may have puzzled you is why running shoes have two extra eyelets at the top.

They’re not there just for fun, though they’re undoubtedly fun – they’re there to be used to tie a runner’s knot. This is also known as heel lock lacing, which gives more clues as to the point of this one. Speaking of what…

What is the point of a runner’s knot?

One of the first concerns experienced runners have when trying on a shoe for the first time is whether it slips in the heel. Even a fairly minor movement in the heel during a run will result in rubbing that causes pain or a blister after a while. This slippage can occur even in a shoe that fits your toes and midfoot perfectly.

The runner’s knot is a way to limit the risk of heel slippage, as it creates a more secure hold around the collar of the shoe. Heel lacing is something trail runners often use because it’s common for the heel to slip on long descents, but all runners can benefit from it if they find their heel slipping.

Does the heel lacing work?

In my experience as a running shoe reviewer, tying a runner’s knot eliminates heel slippage about 90% of the time I’ve noticed it on a shoe, and while it doesn’t completely fix the problem, that usually makes it much better. It’s not a guaranteed fix – some running shoes just won’t fit your heel – but it’s definitely worth a try before giving up on a shoe.

How to tie a runner’s knot

Step 1: Create curls

(Image: © Nick Harris-Fry/Future)

Start by creating a loop with each shoelace by threading it through the extra eyelet on the same side – don’t cross as you would when lacing a shoe normally. Pull the laces until the loops on each side are quite small.

Step 2: put on the lace

(Image: © Nick Harris-Fry/Future)

Thread the shoelace through the loop on the opposite side and pull it tight enough.

Tie your shoelaces as usual from there.

A runner's knot

The Finished Runner’s Knot (Image credit: Nick Harris-Fry/Future)

When you first tie a runner’s knot, you’ll probably be squeezing it really tight — the idea is to secure the heel, after all — but it can create uncomfortable pressure on the top of your foot from the laces. Do not abandon. It may take a few tries to find the right balance between safety and comfort.

The only other downside to the runner’s knot is that it can make a shoe harder to get on and off, but buying a shoe horn is a small price to pay to avoid heel blisters.