Ever wondered what the heel-to-toe drop is all about?
Then you have come to the right place.
Choosing running shoes is tricky. And it’s a personal affair.
Many factors influence your choice, from physiology, training goals, and personal preference. What works for your friend might not work for you.
That said, understanding running shoes is one step in the right direction when it comes to finding the right pair. And one of the most important things to understand about running shoes is what’s known as the heel-to-toe drop.
In this article, I’ll discuss what the heel-to-toe drop is all about and why it matters in running shoes. I’ll also explain how to determine the most suitable drop height for you.
Sounds great?
Let’s get started.
What is The Heel To Toe Drop?
First things first, what is the heel-to-toe drop?
Also known as the shoe offset, heel differential, or HTD for short, the heel-to-drop refers to the difference in height between the heel and the forefoot of an athletic shoe.
Let me explain.
The measurement is taken around the base of the heel and the middle point of the forefoot, and it’s usually provided in millimeters, going from 0 to over 14mm in running shoes.
A drop of zero would mean that heel and the ball of the forefoot would be more or less at the same height as the ground when seated in the shoe.
On the other hand, a running shoe with 15 mm of material under the heel and 5 mm of material under the forefoot would have a heel drop of 5 mm.
In this case, the heel sits ten millimeters higher than the forefoot when wearing the shoe.
Running shoes are also broken down by the level of heel drop they have. The four most common groups you’ll encounter include zero-drop, minimalist, moderate, and high drop shoes (more on this later).
The Purpose Behind Drop Height
The goal behind a shoe’s drop is to limit stress on certain parts of the body by intentionally keeping the foot in a specific position.
For example, the lower drop, the easier it’ll be to land on the forefoot or midfoot while running.
Let me explain more…
Low Vs. High Drops
The lower the drop, the more likely you’ll strike on the forefoot or midfoot. That’s why some experts recommend runners with chronic knee problems to go for a lower drop shoe to avoid hyperextension and take some of the pressure off the knee.
However, although this takes some of the pressure off the knees, it may put more stress on the lower leg.
After all, the impact stresses have to go somewhere.
Conversely, a higher-drop shoe may work best for runners with lower leg issues, such as in the calves, Achilles, foot, or ankle—while transferring more impact to the knees and hips.
HTD Vs. Stack Height
Before I go any further, let me clearly state that stack height and heel drop are not the same thing.
Stack height refers to the cushioning inside of the shoe between the bottom of the foot and the ground. It measures the distance from your foot to the ground, typically based on the amount of material under the foot.
Stack height can range from minimal to maximal, and this measurement usually correlates with how much cushioning that a shoe has.
That’s why a shoe with less cushioning will have a lower stack height—and vice versa.
Additional resource – Can you run with a broken toe?
It’s Not A Golden Rule
Although heel-to-drop is important, it’s by no means the only metric to consider. It’s actually just one among many.
The shoe volume, structure, firmness, amount of cushioning, as well as your training goals and preferences all have a say. Even if a pair of shoes have raving reviews, it means nothing if they don’t fit your foot.
The Importance of HTT Drop
First things first, I’d like for the record to clearly state that there’s no conclusive scientific EVIDENCE that a shoe’s drop affects overall injury rates.
In fact, the evidence is, at best, anecdotal.
The only research I found is a 2016 study reported by the American Journal of Sports Medicine that tracked 553 recreational runners for six months. The participants were divided into three groups with different heel to toe drop from the least to the most, consisting of:
- Group A – 10 millimeters drop
- Group B – 6 millimeters drop
- Group C – 0-millimeter drop.
All the runners monitored their training load as well as a sustained injury during the six-month period (that involved one or more days of missed runs).
In the end, the injury rate was quite the same regardless of which type of shoe they wore—roughly 25 percent of each group reported a running injury during the experiment.
The main conclusion of the experiment was that injury risk not only depended on the shoes used but also on training frequency.
Occasional runners (those running less than once a week for six months or more of the previous year) had a lower injury risk running in a shoe with 0mm or 6mm heel-to-drop than shoes with a 10mm drop.
For more frequent runners (those running at least once a week or more for more than six months of the previous year), this risk was reversed—as in, they reported fewer injuries when using the higher heel-to-drop shoes.
My Opinion?
Scientific proof aside, I’d still recommend that you pay attention to your shoe’s drop, especially if you have a history of overuse injury.
The HTT drop is the reason why one pair of shoes might feel off, and another might be right for you. Different drop levels are better for different runners.
Range of Drop levels in Running Shoes
There’s a wide range of drop levels in running shoes, from the absolute minimalist shoe to the extremely cushioned ones.
Drop levels are typically broken down into the following:
Zero Drop Shoes – Roughly 0 millimeters
Most shoes within this category are often labeled as “barefoot” shoes as they embody the essence of the minimalist movement. In fact, these have gained a lot of steam after the book Born To Run by Christopher McDougall was published a few years ago.
It is believed that these shoes mimic how your foot should sit on the ground, as naturally, it lies flat.
In zero drop shoes, the heel and forefoot are on the same plane. They’ve little to no cushion in the heel pad and a minimal later of material between the shoe and the ground.
I’m a big advocate for zero drop shoes, but I won’t recommend them for beginners. These shoes are for runners who have been around the running block for a while and have already developed proper running technique and habits.
If you’re a beginner runner, you’re better off running in shoes that offer plenty of support and cushioning to protect your legs from the impact of the sport.
Some of the most popular brands that make reliable drop running shoes include:
- Topo
- Altra
- Merrel
Low Drop – to 1 to 4 millimeters.
Typically referred to as minimalist shoes, these have a lot in common to zero drop shoes but with a bit more structure—even though they feel very flat to most runners.
The heel sits roughly four millimeters over the toes, which provides a slight forward momentum.
The low drop shoes are for the runner who seeks more of the barefoot running experience but is not yet ready for zero-drop. These also encourage a forefoot or midfoot strike pattern.
Mid Drop – Around 5 to 8 millimeters
This is the compromise zone. Shoes within this category are not minimalist neither extremely cushioned.
Mid drop shoes work well for a wide variety of runners, making the typical range for most running shoes.
High Drop – 10 millimeters and above
High drop shoes are your typical stability shoes. In fact, any shoe with a drop higher than ten millimeters is a relatively firm and motion-controlled shoe.
If you have lower leg issues, such as Achilles tendonitis or tight calves, high drop shoes may help.
Shoes within this category send more impact to your knees and hips but are more merciful on the lower legs, including the foot, ankle, Achilles tendon, and calf.
Of course, I couldn’t find any reputable study to back this, but there’s a lot of anecdotal evidence, do so why not give it a try.
To Conclude – The Best Heel To Toe Drop
Since HTT is a personal matter, there’s no such thing as a magical formula that works in general.
The best way to tell which HTT drop works the best for you is to pay attention to your body.
This is because various heel drops impact various body parts, as I have previously explained.
As a rule, the ideal shoe should feel like an extension of your feet the moment you wear them.
When it comes down to it, heel drop is not a deal maker or breaker.
It’s not the most important factor to consider when choosing running shoes.
Instead, let fit, comfort, and functionality be the main consideration. Find out more about how to choose your first running shoes in my beginners’ guide.
