Have you ever considered, in great detail, exactly what makes a sneaker feel comfortable? Factors like fit and cushioning technology are some plausible influences, but one of the key elements is actually much simpler than that: the insole. If you’ve forgotten what an insole is, take a look back on our Shoe Anatomy 101 lecture.
The humble insole is perhaps one of the most significant factors in how a shoe feels. Insoles can totally change fit, flexibility, breathability, and anything else contributing to overall comfort. For this instalment of Material Matters, we take a deep dive into OrthoLite, the self-proclaimed leading manufacturer of insole foams. For a company that reportedly produces over 500 million pairs of insoles each year, their online presence is surprisingly small.
Based in Amherst, Massachusetts, OrthoLite was founded in 1997, and quickly established a very straightforward mission: ‘To help brands build better shoes by making them more comfortable’. In order to do this, they launched an in-depth focus on insoles.
The company introduced an industry first: insoles made from open-celled polyurethane (PU). When you look at the surface of an OrthoLite sole, you might think it resembles a typical kitchen sponge – which in a rudimentary sense is true. Open-celled foam is breathable and elastic – i.e. it tends to return to its original form after compression or bending.
These are perfect properties for something like shoe insoles. One of the main factors affecting a shoe’s gradual decline in comfort is the insole flattening out, because of its repeated compression from body weight and movement. OrthoLite’s open-celled composition resists compression, helping it to remain comfortable for longer. In fact, OrthoLite claim their insoles compress less than five per cent over time. This also means shoes fit more consistently throughout their lifetime.
Open-celled foam’s breathability is logical for footwear, as OrthoLite insoles are generally overlaid with fabric. This helps wick moisture, which ‘breathes’ through the foam. After all, dry feet are comfortable feet. The foam’s structure also means it is easily washable, a feature that OrthoLite are quick to highlight.
To borrow an industry term, OrthoLite is considered an Original Equipment Manufacturer (OEM), which means they supply components – i.e. insoles – for footwear companies to make shoes. This is beneficial for both parties, as shoe companies save money by not needing to produce insoles, while OrthoLite can focus on being a specialised manufacturer. According to OrthoLite, over 350 different footwear companies use their insoles.
Some notable examples include the latest New Balance 990v5 – the first in the almost four-decade strong series to feature co-branded OrthoLite insoles. Nike have worked with OrthoLite since 1997, but it’s not just performance products using these popular insoles. A contemporary example is the Converse Chuck 70, where the spongy insole is what gives the modern silhouette all of its comfort. Even current productions of adidas’ Stan Smith, and a wide variety of Lacoste’s casual offerings, use OrthoLite insoles.
OrthoLite use a variety of methods to manufacture their insoles. The simplest way is die cutting foam slabs – think insole-shaped cookie cutters. More advanced designs involve moulding the foam to shape, particularly if it involves different densities for varied cushioning levels. Furthermore, features like flexible siping, or textured foam surfaces, are additional production steps.
OrthoLite’s commitment to sustainability has been present since the very beginning. All insoles produced by the company contain at least five per cent recycled rubber: that’s what forms the idiosyncratic black speckling through the foam, visible from the underside of the insoles. To further their sustainability efforts, the company hired Skip Lei as vice president of innovation and strategic partnership between 2015 to 2018. A 31-year Nike veteran, Lei’s expertise was leveraged to make inroads with hybrid foams, and incorporating 15 per cent production waste foam – think cut-offs – into new insoles. Added to the five per cent recycled rubber already used, the insoles now consist a total of 20 per cent repurposed materials. Future indications seem to suggest that that figure might rise even higher in the coming years. At the start of 2019, OrthoLite announced development of an insole range made from 98 per cent post-production waste!
OrthoLite currently produce 13 different types of insoles – in multiple colours – for footwear applications, ranging from responsive and high-performance sports shoes, to extremely casual use. However, it’s not just insoles that OrthoLite foam is useful for. Its sponge-like qualities can also be used in the upper’s lining and tongue padding to mould and cradle the foot. Beyond footwear, OrthoLite foam can also be used in the padding of protective sports equipment.
So, next time you’re shopping for a new pair of sneakers, take a look at the insoles before you put your feet inside. If you see and feel soft foam, chances are you’re about to try an OrthoLite insole.