Joints & Landing Gear

The ground doesn't care
about your joints.

Every step, the flat ground loads your subtalar joint axis (the pivot between your heel bone and the bone above it — angled at 42° of inclination and 16° of deviation) at the wrong angle. The rest of the kinematic chain compensates. That compensation has a cost — and it compounds at roughly 8,000 steps per day.

See the independent data ↓

T-100

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Not an insole. Landing Gear. Built as a runway — where your foot knows exactly what to do the moment it touches down.

$64.95 / pair

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Section 01 — The Mechanics

Flat ground runs
a kinematic chain.
Every joint is downstream.

The subtalar joint is the drive shaft of human gait. It sits at 42° of inclination and 16° of deviation — the exact geometry Landing Gear is built around (Manter, 1941). When the ground forces the STJ to operate outside that geometry, every joint above it receives a compensatory load signal.

42°/16°

STJ Axis Geometry

The precise inclination and deviation angles of the subtalar joint axis, established by Manter in 1941. Flat ground doesn't accommodate this geometry.

~8,000

Steps Per Day

Average daily step count. Each step on a misloaded STJ axis is another compensatory signal propagating up through the ankle, knee, hip, and lumbar spine.

25 lbs

Joint Pressure per 5 lbs

Every 5 pounds of extra body weight adds approximately 25 pounds of pressure on your weight-bearing joints. The STJ axis geometry determines how that load is distributed — or misloaded — across the chain.

✓ When the STJ axis is loaded correctly

The foot and lower leg act as a spring.

When the heel strikes and the STJ rotates through its 42°/16° axis, pronation stores kinetic energy — and the supination that follows releases it as forward propulsion. The foot, the Achilles, and the lower leg work as a compliant spring system. Impact is absorbed, redirected, and returned as motion.

✕ When the STJ axis is misloaded

The impact shoots straight up the chain.

When flat ground forces the STJ outside its optimal axis, the spring mechanism doesn't engage. The energy from each heel strike has nowhere to go — it doesn't convert into propulsion, it transmits upward as raw impact force. Ankle. Knee. Hip. Lumbar spine. Every joint above absorbs what the foot failed to redirect.

What Happens When the STJ Axis Is Misloaded

Subtalar Joint

Flat ground forces the STJ to pronate past its 42°/16° optimal axis. This is the root cause — not a symptom.

↓

Ankle & Tibia

Excessive subtalar pronation drives tibial internal rotation. The lower leg torques inward on every step.

↓

Knee

Tibial internal rotation increases the knee adduction moment — the inward torque the knee resists on every step. The knee is not a rotational joint; it absorbs what the STJ below it generates.

↓

Hip & Lumbar Spine

Compensatory hip adduction and lumbar side-flexion absorb what the knee couldn't redirect. The chain terminates somewhere. It always does.

Section 02 — The Science

The theoretical model behind conventional arch support was declared invalid in 2023.

Behling et al. published a systematic review in Biological Reviews (Cambridge Philosophical Society) examining the mobile adaptor–rigid lever model — the biomechanical framework that has guided footwear and orthotic design for decades. Their conclusion changed the foundation of the field.

Behling et al., 2023 — Biological Reviews, Cambridge Philosophical Society

"The mobile adaptor–rigid lever model…has been used widely in clinical and research settings to inform footwear design, orthotic prescription, and gait analysis. However, this model lacks a rigorous biomechanical foundation."

The industry built products around a static model of the foot — the arch as lever, the heel as fulcrum. But the foot doesn't function as a rigid lever. It functions as a dynamic kinematic system driven by the subtalar joint axis. Supporting the arch doesn't change the geometry of the axis. It doesn't change what the ground does to the chain above it. Landing Gear addresses the geometry first.

M-100 — Maximum BioMechanica

The deeper geometry. The stronger result.

For high-demand applications — all-day standing, high-impact work, full kinematic chain loading — the M-100's deeper 42°/16° geometry produces the strongest BioMechanica result.

M-100 M-100 Landing Gear Maximum geometry · Black / Grey / Orange $64.95

Not sure which to start with? T-100 available at $64.95 — recommended starting point for most buyers.

Section 03 — Independent Study Data

The BioMechanica study.
31 subjects. 3D motion capture.
Independent Portland lab.

Dr. Martyn Shorten Ph.D., 2019. Subjects walked on a force plate while 3D motion capture tracked STJ axis alignment in real time. Each measurement was plotted against the optimal 42°/16° geometry. Here is what the data shows.

Condition	Subjects in Optimal STJ Range	Out of 31 Total	Result
Barefoot	3 subjects	10% of test group	Baseline. The human foot on a flat, modern surface — the floor it didn't evolve for.
T-100 Landing Gear	19 subjects	61% of test group	Standard geometry. Recommended starting point for most buyers. 6× improvement over barefoot.
M-100 Landing Gear Maximum	28 subjects	90% of test group	Deeper geometry. Strongest BioMechanica result. 9 in 10 subjects measured in optimal STJ alignment.

BioMechanica study: Dr. Martyn Shorten Ph.D., BioMechanica LLC, Portland, OR, 2019. Independent 3D motion capture laboratory. n=31. Measurement criteria: subtalar joint axis within optimal 42°/16° geometry range during mid-stance loading phase. "9 in 10" framing applies to M-100 result (28/31 = 90%). Joint pressure stat: Pennsylvania Orthopedic Associates — "Every five pounds of extra body weight increases the pressure on your joints by about 25 pounds." paorthopedics.com

Section 04 — What Most Products Miss

Shape vs. geometry.
A photo vs. a movie.

Conventional insoles are built around the shape of the foot at rest — a static photograph. The subtalar joint doesn't operate at rest. It operates in motion. Landing Gear is built around the geometry that governs that motion.

Feature

✕ Conventional Insoles

✓ Landing Gear

Design reference

✓

Static foot shape (photo)

✕ Yes

✓ No

42°/16° STJ axis geometry

✕ No

✓ Yes

Independent 3D motion capture validation

✕ No

✓ Yes — 31 subjects

Addresses kinematic chain loading

✕ No

✓ Yes — STJ axis first

Consistent across left/right

✕ Variable

✓ Matched geometry

Based on a declared-valid model (post 2023)

✕ No — model invalidated

✓ Yes — motion-based

Put the right geometry under your feet.
The ground isn't going to change.

T-100 Landing Gear is the recommended starting point — the same 42°/16° STJ axis geometry, independently verified in 3D motion capture. Put them in your shoes. Take a step.

Get the T-100 — $64.95

Questions? We're here.

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Go Deeper

Foundation

What Is Landing Gear?

The 42°/16° geometry. What it means. Why the name is literal.

Read →

Mechanism

Why It Works

The four-subsystem model: drive shaft, hydraulic damper, rubber band, servo.

Read →