3 Arches

"Of all the bones in the foot, the Talus, Cuboid and Middle Cuneiform are structurally very important. If one or more of these three bones is out of alignment, the structural integrity of the arch it supports, and in turn the strength and stability of the entire foot becomes compromised."
- ​Thomas Michaud, 1993.

Medial longitudinal arch

Spring system
Stores energy for driving force
Shock absorber
Keystone: Talus

Lateral longitudinal arch

Bears body weight
Provides balance
Body stabilizer
​Keystone: Cuboid 

Transverse arch

Supports the arch
Provides flexibility to arch
Arch maintainer
​Keystone: Middle cuneiform

3 Structures

Foot types are generally classified into one of three categories:
​flatfoot, neutral, and high arch.

Flatfeet

Structural or Functional
High stress on the heel
In-toeing or very out-toeing
X-shape legs
​High risk of hip pain

Neutral

Great feet!
Please take care of them

High arch

Mostly starts at age 3 
High stress on lateral ankle 
Out-toeing
O-shape legs
High risk of plantar pain

3 Rotations

When your foot touches the ground, it will slightly rotate 3 times in order to absorb shock, maintain balance and provide driving force. This only takes about 0.7 seconds.

Heel contact

First rotation
​ (15% stance phrase of gait)
Shock absorb 
Muscle focus: Heel and Calf

Midstance

Second rotation 
(35% stance phrase of gait)
Maintain balance
Muscle focus: Hip and waist

Propulsion

Third rotation
​(50% stance phrase of gait)
​Provide driving force
Muscle focus: Thigh and Knee