Shoe Comfort

Design Develop and Test The Best Insoles

October 26, 2023

Footwear brands need to know the right process to create a top performing insole. The right process improves your customer's experience, creates easier workflows for your product development team, and saves you money. In this newsletter we leverage Heeluxe's experience in helping 100s of footwear brands make more comfortable insoles to provide the most efficient way to create a top performing insole.

Step 1: Figure out your foams

As discussed in part 2 of our insole series, Foam is your Friend! It's easy to be overwhelmed by all of the possible choices for insole foam. Identifying the best foam for you to use is easy when you follow this process.

First the footwear brand must identify the foams that meet their pricing needs and works with their current manufacturing process. It's common to have 15-30 possible foams after this process. How do you narrow down these options to the best 1 or 2 insoles?

The second step in determining the best foam is quantifying its cushioning performance. A fast and affordable option is Impact testing with Heeluxe. This testing identifies the best performing foams from your options and compares them to our database of 100s of insoles. The best foam you're considering may not perform well against our database. In that case, it's best to find other foams to use for your insole.

Heeluxe's impact testing utilizes the ASTM 1976F test protocol. We test all insoles with a 3Kj ("low") setting on top of a 12.5 mm 85A rubber block. This rubber block replicates the performance of a firm midsole under your insole.

Fig 1: Finding the best foam is easy when you compare your foams to a big database.

Step 2: Confirm your Contours

Contour of your insole is critical for comfort. The shape of your heel cup and location of your arch support will increase your customer's satisfaction if they are designed well. If they are poorly designed the bad shape will be less comfortable and is a waste of the top-quality foam you chose.

By combining details on the type of shoe you are making, the average shape of your customer's foot, and Heeluxe's insole database you'll be able to efficiently design the contours of your insole.

Step 3: Bring in the Human Testers

This step is very important to ensure your well-designed insole works well with your brand's unique shoes. Testing your new insole in all shoe constructions that it will go into ensures that your customer has a consistent comfort experience. During this testing you need to collect data on cushioning (plantar pressure) using sensors and perception feedback from humans that represent your target customer. At Heeluxe we call this Comfort Testing. We'll often include fit testing to ensure your insoles do not change the volume of your shoe. Comfort testing only takes 2 weeks, so it is easy to fit into your development timelines.

During the human testing you MUST test your insoles on the different midsoles you will use the new insole in. A firm or inflexible shoe may need softer insole cushioning than a super soft midsole in order to provide a consistent comfort experience. For this reason, testing your new insole in 2 different compounds during human testing is recommended.

Step 4: Make The Comfort Long Lasting

We have all experienced an insole that feels amazing when we first purchase the shoe and then it loses its comfort after a few days of wear. Not only does the cushioning performance change, but a compressed insole also changes fit!

The best way to find out how long your insoles will last is to use Heeluxe's Time Machine Rapid Durability testing. We'll use this test to simulate 100 miles of walking or 150 miles of running in only 5 days. Once we have broken down your insole, we can re-test it on the Impact tester mentioned above to find out how fast your insole is losing its cushioning. It's also possible to calculate how many miles your insole will last.

Let's Make Amazing, Top-Performing Insoles!

This 3-part insole series has covered why insoles are important for comfortable shoes, the key parts of insoles, and now how to design and test a top-performing insole. Now that you have this amazing information, the Heeluxe team wants to see your insoles in the footwear world! We're always here to help you with any of your insole testing questions, feel free to contact us anytime