Lab Rat

What Is Heel Drop?

Running shoes are constantly evolving – and even though the barefoot running trend has somewhat subsided, it did spur shoe designers to think about the platform of the shoe and the heel drop. So as runners face a wide selection of shoes – another term has been thrown into the mix. What does heel drop actually mean?

David Korell, footwear merchandiser for New Balance Canada, along with Matthieu Trudeau, biomechanics research scientist at Brooks Running, weighed in.

What does heel drop mean?

“Basically it’s the difference in height in millimetres between where the heel and forefoot sit in the shoe,” says Korell. “The higher the number, the greater the differential between where the heel and where the forefoot sits, so there is more of a tilt or slant. The lower the number, the f latter the shoe or the heel and the forefoot sit at the same height. So a drop of zero means the heel and forefoot are level.”

However, Trudeau points out that when you measure the height of the heel and forefoot in a shoe it might be a zero drop, but the foam in the shoe compresses when you load it. “So the drop may not remain zero in a dynamic situation. For a heel striker, if you put some force on the heel, it will actually drop beneath that zero drop, so it will be a negative drop. For those who may run in a zero drop shoe that is very cushioned, it won’t feel that good in the transition. That’s one thing to keep in mind.”

What are the effects of a heel drop?

The minimalist running movement inspired designers to think about the platform of the shoe. The thicker the heel, the more likely you may heel strike and land in front of your hips, which some people in the running community believe leads to injury. Others feel that in shoes with less cushioning often associated with low heel drop shoes you are more likely to land on your midfoot, under your hips, which is similar to the way you would run barefoot.

But as Korell points out, “we probably could run barefoot but man created concrete and asphalt – so now we need cushioning underfoot. A midfoot striker is going to be seeking out a low drop shoe, and we say a drop of 4 mm or less is generally considered a minimalist shoe. The thickest drop is typically 12 mm and the thinnest 0 mm, with the industry median being 8 mm these days.” However, the effect of the heel to toe drop hasn’t been studied that well, says Trudeau. “The cushioning is often confused with the drop of the shoe, with a high drop being associated with more cushioning. We did a study a while back at Brooks and found not much changes in the biomechanics above a 4 mm drop, so between 4 mm and 12 mm, runners behaved similarly.”

What do elite athletes wear?

Competitive distance runner and physiotherapist Katie Snowden says, “From a performance standpoint, footwear choice is much more significant for a performancelevel runner versus an average runner. For performance I would race in a minimalist shoe. You’re just much more efficient. You don’t seem to over stride as much when you’re up on your toes. You’re lighter on your feet and your turnover is faster.”

How important is heel drop?

Korell and Trudeau agree that fit and feel play an important role in choosinig the shoe’s drop ratio. “Materials will vary from shoe to shoe – and as long as runners are steering towards a neutral, stable or a lightweight shoe according to their mechanics – plus or minus a 2 mm heel drop – you’ll be OK,” says Korell.

And if you’re tempted by minimalist footwear with a drop of 4 mm or less – do it gradually, injects Trudeau – very gradually.