Shoe Fit

Designing for Optimal Heel Fit

November 1, 2022

Heel fit is often overlooked in many shoes tested at Heeluxe. Bad heel fit reduces comfort, increases the likelihood of blisters, and causes early breakdown of a shoe. Our lab data on shoe fit reveals a few simple solutions for improving heel fit.

Many brands don’t put much attention to it until they get complaints from customers or their fit testers. Heel fit isn’t as important as ball and toe width when considering shoe comfort, ill fitting heels will ruin a person’s experience in a shoe. Before covering the solutions for bad heel fit, let’s review its origins.

During the activities of walking/running/jumping/etc when our heel will lifts off the ground the shoe will need to move with the heel. If this does not happen, the heel of our foot slides upwards relative to the shoe. This “piston-ing” of the heel causes friction in the skin and results in soreness and blisters. Not good! Similarly, if your shoe has a thick, soft insole it could allow the heel to “piston” downwards in the shoe when our foot hits the ground with every step.

To reduce piston-ing of the foot, the most effective strategy is to have good fit around the instep of the shoe. Most brands have heard the Heeluxe saying, “If you want good fit, think navic” in reference to the navicular bone in our instep. The Navicular is the green bone in the foot image below. It’s located around where the second eyelet from the top is located on most lace up shoes. By having a secure fit here, there is much less opportunity for the heel to piston in the shoe.

Heel collar padding is also effective at optimizing heel fit. Thick, soft padding will follow the contours of our heel. For those customers with wider heels or swollen ankles, the heel collar padding compresses giving their feet the same type of comfort as someone with a smaller ankle. Because of this, heel collar padding is a much more effective than heel counters to get optimal heel fit. Below are two examples of shoes thin heel collar padding (Left) and thick heel collar padding (Right).

If your brand wants the sleek look of no heel collar padding, there are ways to get good heel fit. Some brands use a small teardrop of foam just below the heel collar to secure the foot but still have a thin sleek profile. Great examples of this are the early generations of Saucony’s Kinvara and the current Under Armour Flow Velociti. The small amount of foam had a great heel fit for many wearers while retaining the sleek look around the ankle. Below is an example of a low top hiking shoe with a well-designed foam teardrop.

The SmartLast system makes it easy to analyze if your heel and instep fit is too loose and prone to fit problems. When you are ready to measure your heel fit, please contact the shoe researchers at Heeluxe