Review of Specialized Masterfit Thermoformed Insoles

When cycling, proper form starts with your feet and how they’re positioned in your shoes. Now firmly established in the field of rider fit, Specialized uses the Retül Fit concept. We’ve tested the system’s custom insoles over several thousand kilometers.

By Guillaume Judas – Photos: 3bikes.fr

Having been established and recognized for several years among cyclists and triathletes seeking to optimize their comfort and performance, Specialized’s Body Geometry Fit posture analysis has been replaced by the Retül posture analysis in recent months. This move formalizes a partnership between the two brands that has been in place since 2012, as Specialized was already using the Colorado-based company’s comprehensive analysis tools before recently acquiring it. Among these various tools is the Footbed kit, which enables the creation of custom Specialized Body Geometry Custom insoles, developed in collaboration with Masterfit.

There’s a lot of information and registered trademarks to mention here, but the key takeaway is the ability to have insoles custom-made to perfectly fit the unique shape of each person’s feet—and for all types of cycling shoes. The benefits? Greater comfort, more power, fewer pressure points under the soles of your feet, and sizing that fits all shoes. A comparison can be made with the Specialized Footbed SL insoles, available at all retailers carrying the American brand. These insoles offer a choice of three levels of arch support (red, blue, or green), which we had been using until now, and are priced at €29.90.

It was thanks to the K7 Bikes store in Monthléry, Essonne—with a technician known locally for his expertise, his ability to listen, and his mastery of the tools provided by Specialized and Retül—that we were able to test the Custom Masterfit insoles. This service is currently available at only six of the brand’s retailers:

• GD Cycles: 4 Rue de la Madone, 71000 Sancé
• CP Bikes: Zone Ecotec, 512 Rue des Peupliers, 74460 Marnaz
• K7 Bikes: Zone d’activité des bourguignons, 31 Rue du Pont aux Pins, 91310 Montlhéry
• Hot Wheelz: 2033 Chaussée de Wavre, 1160 Auderghem, Belgium
• Cycles Joliat: 17 Rue Saint-Maurice, 2852 Courtételle, Switzerland
• Les Cycles Thevenaz: 21 Rue des Arts, 1450 Sainte-Croix, Switzerland

The Molding Process

The insole prep kicks off by positioning the rider on the Retül Footbed, which is basically a padded stool paired with a foot-moulding machine. Under the footrests sit hundreds of tiny beads and an air pump. You then stand on the footrests to create an impression and, crucially, fill the space with your arch. Once you’re in position, the air pump locks the beads in place beneath the footrests, clearly capturing the shape of your feet. Note that the two feet may differ slightly from one another, which ultimately makes the concept of thermoformed insoles far more effective than insoles with an adjustable arch support. The insole is then selected based on the size of the feet.

It consists of a thermoformable bottom layer made of a type of resin, with the forefoot section being semi-flexible and the section extending from the midfoot to the heel being much stiffer. The upper part of the insole, where the foot rests, is made of fairly dense foam.

The fitter then uses a heat gun to soften the insoles, then positions them on the previously made mould.

The subject then places their feet back on the insoles for a few minutes, until they cool and harden, taking their final shape. The technician then adjusts the fit of the insoles inside the shoes by trimming the edges slightly if necessary.

Testing Compared to the original insoles, the Specialized Masterfit insoles are slightly heavier. Expect an additional 30 g per insole for a size 39. This isn’t a problem from our perspective, especially since they adapt immediately. You’re immediately enveloped in plush comfort, even though the insole is rigid across nearly two-thirds of its length—from the small shell formed around the base of the heel to just in front of the arch of the foot.

The reason for this is that the shoe is perfectly molded to the shape of the foot. However, the design itself doesn’t directly conform to the shape of the metatarsals, since the forefoot remains relatively flexible, leaving the front of the foot fairly unrestricted. It’s only after several hundred kilometers that the dense foam naturally molds to the shape of the big toe, where there’s the most pressure in certain situations. Since we were already using insoles with arch support (though not customized in terms of placement), our first few rides revealed a slight feeling that the shoe lacked stiffness in that specific area. It’s not that the Masterfit insole lacks rigidity here, but simply that the pressure points on the inside of the foot are perfectly distributed. While the first few rides primarily highlight comfort and a more evenly distributed, less painful fit in the shoes (thanks to the foot’s positioning, which is ideally secured), it’s over time that you come to appreciate the effectiveness of the design.

It’s a feeling of being perfectly secured and supported in shoes that are already stiff to begin with

First, during pure strength exercises, with the impression of avoiding power loss due to foot flexion. Then, when incorporating high-intensity exercises, with the sensation of being perfectly secured and supported in shoes that are already stiff to begin with. As for overheating or feeling cold—which are often mistakenly attributed to the shoes’ ventilation capabilities—this is, in our view, irrelevant. Of course, at first glance, the thermoformed insoles appear less breathable than the original insoles, whose ventilation holes align with those in the carbon insoles. But the sensations of burning feet or numbness are primarily the result of venous stasis caused by excessive pressure points, either above or below the foot. With Specialized Masterfit thermoformed insoles, pressure under the feet is perfectly distributed across the entire sole, so this sensation is virtually eliminated.

In short, while the concept itself may seem a bit pricey (how often do we hear that getting a postural analysis is “pointless”?), these custom insoles are an undeniable plus in terms of comfort and effectiveness.

-> SEE ALSO: All our gear reviews