The Science Behind FlowCore

The Science

Why Liquid Beats
Everything Else

The science behind FlowCore™ isn't new. It's 2,500 years old. We just put it inside your shoe.

The Principle

Archimedes' Principle of Fluid Dynamics

In 250 BC, Archimedes discovered that fluid moves to the area of least resistance and greatest need. When pressure is applied to one point in a contained fluid, that pressure is transmitted equally in all directions.

This is the exact principle inside every ArchGlide FlowCore™ insole. The liquid glycerin inside the sealed TPU chamber responds to pressure from your foot by flowing to the areas that need support most. It's not programmed. It's not mechanical. It's physics.

🌊

"Fluid moves to the area of least resistance and greatest need."

Archimedes, 250 BC

Step by Step

What Happens Inside Your Shoe
With Every Step

Cross-section showing liquid glycerin flowing inside ArchGlide FlowCore beneath foot anatomy
01

Heel strike

When your heel hits the ground, your body weight creates a high-pressure zone under the heel. The glycerin is pushed forward toward the arch and ball of the foot, cushioning the impact before it reaches your ankles, knees, and spine.

This is why ArchGlide reduces joint impact. The liquid absorbs and redistributes force that would otherwise travel straight up your skeleton.

02

Midfoot transition

As your weight shifts forward through the stride cycle, the glycerin flows with it. Your arch, which is typically unsupported by flat insoles, is now filled from below by liquid that self-levels to match your exact anatomy.

No two feet are the same. Even your left and right foot have different arches. Liquid adapts to both automatically. Rigid orthotics cannot.

03

Toe push-off

When you push off your toes, the glycerin flows back toward the heel, preparing for the next step. This continuous cycle creates a massaging action that boosts circulation in the foot with every single stride.

Clinical studies on glycerin insoles show circulation to the feet and lower extremities can be significantly increased during use.

04

Repeat, forever

Unlike foam that compresses permanently after the first few hundred steps, liquid cannot be compressed. The glycerin performs identically on step 1 and step 1,000,000. There is no break-in period and no breakdown period.

This is why ArchGlide outlasts 3-4 foam insoles. The material itself is immune to the forces that destroy every other insole on the market.

Material Science

Why Every Other Material Fails

EVA Foam

Dead in weeks

Compresses permanently under body weight within 2-4 weeks

Once compressed, provides zero cushioning

Absorbs moisture, breeds bacteria

Must be replaced monthly

Solid Gel

Flattens over time

Deforms under sustained pressure over 1-3 months

Cannot flow or adapt to foot shape

Static cushioning only, no circulation benefits

Traps heat, makes feet sweaty

Rigid Orthotics

One shape, one shoe

Molded at one moment, but feet change daily

Only fits one shoe, $300-800 each

Support but zero cushioning

Can create new pressure points

ARCHGLIDE FLOWCORE™

Liquid Glycerin

Alive, always

Cannot compress, identical on day 1 and day 365

Self-leveling, adapts to every foot in every shoe

Continuous micro-massage boosts circulation

Natural thermal insulator for all seasons

The Material

What Is Glycerin?

Glycerin (also called glycerol) is a naturally occurring compound found in all animal and vegetable fats. It is a thick, clear, odorless liquid that is completely non-toxic and hypoallergenic. The FDA classifies glycerin as Generally Recognized as Safe (GRAS). You encounter glycerin every day in food, skincare, toothpaste, and pharmaceutical products.

What makes glycerin ideal for insoles is its viscosity. It is 50 times more viscous than water, which means it flows slowly and heavily rather than splashing. This density provides cushioning and support that water or thin fluids cannot.

Viscosity
50x water
Dense enough to cushion, fluid enough to flow
Toxicity
Non-toxic
FDA GRAS rated, food-grade purity
Thermal
Insulating
Absorbs heat in summer, retains warmth in winter
Durability
Permanent
Cannot compress, degrade, or break down
Allergens
Hypoallergenic
No known allergic reactions
Compression
0%
Returns to original volume instantly
ArchGlide FlowCore insole anatomy diagram with features labeled

Construction

Three Layers.
Engineered Together.

Top Layer

Woven polyester fabric

Breathable, moisture-wicking surface that sits against your foot. Soft to the touch, durable under friction. Machine washable.

Core

Sealed TPU chamber with liquid glycerin

The heart of FlowCore™. A thermoplastic polyurethane bladder filled with 100% pure food-grade liquid glycerin. Pressure tested and reinforced at all seams.

Base

TPU structural base

Provides the structural foundation. Thin enough to fit any shoe (6mm total), rigid enough to maintain the chamber's shape under load.

6mm
Thickness
~100g
Weight
XS-XXL
Sizes

Conditions

How FlowCore™ Addresses
Common Foot Conditions

🦶

Plantar Fasciitis

The glycerin's continuous flow stretches and releases tension on the plantar fascia, replicating the effect podiatrists recommend. The more you wear them during the day, the better your feet feel in the morning.

Heel Pain & Heel Spurs

Liquid distributes body weight away from the heel's pressure point. Instead of concentrated force on a hard surface, glycerin disperses it across the entire foot.

💧

Diabetic Neuropathy

The massaging action of flowing glycerin significantly increases blood circulation to the feet. Neuropathy is a circulatory condition, and increased circulation is one of the primary therapeutic approaches.

🦴

Lower Back, Knee & Hip Pain

Foot misalignment cascades upward. By equalizing pressure at the foot level, ArchGlide corrects the foundation that affects posture, gait, and joint stress throughout the body.

🏥

General Foot Fatigue

Standing on hard surfaces causes fatigue because feet absorb repeated impact without recovery. Glycerin's shock absorption reduces cumulative impact load on your feet, ankles, and legs.

📐

Flat Feet & Fallen Arches

Because glycerin is self-leveling, it fills the arch gap from below regardless of how low your arch is. Unlike rigid supports that assume a universal arch height, the liquid adapts to your anatomy.

The Foot Pain Epidemic

77%
of US adults experience foot problems
Source: APMA
2M+
new plantar fasciitis cases per year
Source: NIH
39%
of Americans report arch pain
Source: KURU 2025
35%
report heel pain
Source: KURU 2025
10%
lifetime prevalence of plantar fasciitis
Source: NIH
5x
higher risk with BMI over 30
Source: NIH

ArchGlide FlowCore™ insoles are wellness products designed for comfort and support. They are not medical devices and are not intended to diagnose, treat, cure, or prevent any disease or medical condition. These statements have not been evaluated by the FDA. Individual results may vary. If you have a serious medical condition, consult your healthcare provider before using this product.

The Science Is Clear.
Feel It For Yourself.

90 days to test the physics. If your feet aren't convinced, we'll refund every penny.

Shop FlowCore™ — $39.95

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