Physical Therapists Using Clinical Analysis To Discuss The Art And Science Behind Running and The Stuff We Put On Our Feet

Post Page Advertisement [Top]


The Monday Shakeout: The Variability of Shoe Drop
By Matthew Klein

This week we talk about the static measurement of heel drop doesn't tell the true story and why a dynamic understanding will help runners (and walkers) best understand this commonly reported specification.


Along with weight, "Shoe Drop" is a commonly reported number in the description of many running shoes. Heel-Toe Drop, Heel Drop or Shoe Drop is defined as the static difference in height between the back (heel) and the front (forefoot) of the shoe. This changes the relative position of the foot within the shoe. A higher heel drop will put the foot in a more plantarflexed position (pointed foot). A lower heel drop will put the foot in a more neutral or relative level of dorsiflexion. Several years ago, the average drop was 10-12 mm. Since the minimalist movement and the current progressions of the maximal movement, that number now averages in the 5-8mm range. A higher drop is known to reduce the range of motion required at the ankle and from the calf muscles. Those with stiff ankles or calf muscles may benefit from a higher drop shoe, although it does place more load into the anterior shin muscles, quadriceps/knee muscles and the gluteal/hip muscles. A lower drop requires greater range of motion and muscle activity from the ankle and calf muscles. Those with good ankle motion, adequate dorsiflexion, good calf strength/power/flexibility and those looking to shift work away from their knee and hip may benefit from a lower drop shoe.

Drop is Dynamic

What many people do not realize is that the listed drop is a static measurement and shoes are dynamic structures when loaded during activity. The high forces during running, which can be anywhere from 4-6x your body weight with each step, will deform all but the most minimal shoes during the stance phase of running gait (foot on the ground loading the shoe). Additionally, different midsole and outsole combinations will compress more or less depending on their cushioning/compliance. Softer materials will compress far more while firmer materials will compress less (although sometimes a shoe can feel firm despite having a lower compliance foam due to the shoe "bottoming out" or you pushing through all the foam too quickly and compressing it). Some shoes now have different densities of foams in different parts of the shoe that may compress differently, further changing the dynamic drop of the shoe. Depending on several factors, the actual dynamic drop of a shoe can vary greatly not only throughout a person's footstrike, but also between different people. 

The Impact of Footstrike

Initial footstrike is one thing that will impact the heel drop. A heel strike will compress the rear portion of the shoe, lowering the drop as the rear foam compresses relative to the front. A forefoot strike will compress the front portion of the shoe, raising the drop as the front foam compresses relative to the back. A midfoot strike should theoretically compress both the front and back at the same time depending on whether you actually load them equally. As the body transitions over the shoe, regardless of where you land first, there will be a transition of load to the front of the shoe. Therefore, as your foot travels under and behind you and the forefoot of the shoe is more compressed, the dynamic or relative drop will increase.

It is for the above reasons that shoes can feel like they have a different drop than what is listed. The listed drop is a static measurement and may not be reflective of what the shoe does or feels like under load. This can make low drop shoes feel like they have a negative drop (heel strike) or a moderate drop (forefoot strike) or high drop shoes feel like they have a moderate drop (heel strike) or extremely high drop (forefoot strike).

How Does Shoe Wear Play a Role

The last factor is shoe wear. As shoes wear down, the foams/materials begin to compress more and lose their resilience (reforming) ability. Depending on where you land and load, that part of the shoe may compress more. This can also make a shoe feel higher or lower drop than listed with time. This is also why drop can feel so different once you get a new pair of the same shoe after wearing out the old one. For all of these reasons and more, this is why we talk about what the heel drop of the shoe actually feels like. It is also why we encourage you not to obsess about this number given its range and variability. 


PAST MONDAY SHAKEOUTS

Science of Sole Width in Shoes
Challenges with Large Toe Spring
Phases of the Swing Gait
Can Running Shoes Reduce Injuries?
The Best Shoes of 2023 for Highly Specific Reasons
Andrea's Favorite Shoes of 2023
David's Favorite Shoes of 2023
Matt's Favorite Shoes of 2023
My Favorite Flat Feet Shoes of 2023
ChatGPT Reviews a Shoe, Volume 2
How Forefoot Rockers Help Toe Mobility
Running with Backpacks
How Much Does Doctors of Running Make?
Changes We're Excited to See
Why Heel Bevels are Natural
Do Heavier Runners Need Different Shoes?
Shoe Rotations for Different Runners
Strength Training to Prevent Injury - A Case Study
On the Impacts of Different Stacked Shoes
The Importance of Heel Bevels in Shoe Design
Low vs. High Drop Shoes
Why is Proprioception Important to Runners?
Best Running Movie Scenes of All-Time, Part 2
Best Running Movie Scenes of All-Time, Part 1
What a Week at DOR is Like
Reflections on Saucony's Running Economy Study
Sustainable is Only Going to Work if It's Good
A Simple Guide to Footwear and Foot Health
Best Flat Feet Shoes by a Flat Feet Runner
How Long Do Shoes Last?

SHOP | SUPPORT DOR

*Using the link to purchase helps support Doctors of Running. Thanks so much!

Ultraspire Fitted Race Belt: The best way to carry your phone and goods on the run. No bounce and various sizes for waist. (Also recommend the Naked belt)
Saysky Running Gear: We were really taken aback by this Scandinavian company's ultra-thin, durable performance clothing
Skratch Recovery, Coffee Flavor: Mental and physical boost post run. Coffee flavor is excellent and goes great straight into a fresh brewed cup
goodr Sunglases: Run in style with goodr's super fun sunglasses.
Feetures Socks: Massively grippy socks that will make you feel more one with the shoe
Amphipod Hydraform Handheld Water Bottle: Perfect for long runs when you need hydration in the summer
Trigger Point Foam Roller: Help get those knots out post-run and feel better for tomorrow
Theragun Massager: This small version is great on the go for working tired legs
Ciele Hat: Our team's favorite running hat of choice!
Fractel Hats: Our team's wider fitting running hat of choice!

FOLLOW DOCTORS OF RUNNING ON SOCIAL MEDIA

Facebook: Doctors of Running
Youtube Channel: Doctors of Running
Instagram: @doctorsofrunning
LinkedIn: Doctors of Running
Strava: Doctors of Running
Podcast: Virtual Roundtable
Pinterest: Doctors of Running

PODCAST

Check out the Doctors of Running Podcast to find more reviews, interviews, and running features from the team.

Visit our Podcast Page
Find us on Apple
Find us on Spotify


Please feel free to reach out, comment and ask questions!
Contact us at doctorsofrunning@gmail.com

NEXT:
Science of Sole Width in Shoes

Bottom Ad [Post Page]