FOOT FUNCTION AND SQUATTING
• The ability to perform an unassisted bodyweight squat is considered a ‘fundamental’ movement skill
• Habitual use of the squat in daily activity as a work or rest position is a natural way to maintain the strength and range of movement required for basic postural and locomotive tasks such as sitting to standing, lifting, walking etc..
• Within the fitness industry, variations of the squat involving increased loads and stability challenges are among the most widely used exercises for strength, conditioning and rehabilitation.
• Despite the health and performance benefits of squatting, the lower back and knees are at risk of injury if loaded inappropriately due to poor technique.
• Correct squatting technique is a skill that can be learnt, and strength can be increased in the muscles involved IF there is adequate STABILITY and MOBILITY in the foot, ankle, knee and hip joints.
• An area that is commonly overlooked in squatting technique is the influence of foot and ankle function, and the movement strategies that occur to compensate for foot and ankle dysfunction.
SQUATTING POSTURE AND FOOT TYPE:
A. Functional Foot: A wide and stable foot with full range of movement at the ankle enables body-weight to remain centered in the base of support (feet) during the entire movement. Good squatting posture can be adopted with minimum compensatory movement in the knees, hips and spine
B. Rigid Shoe-shaped Foot: Lack of toe function and restricted range of movement in the ankles causes bodyweight to drift backwards onto the heels. In a deep squat (hips below knees) the pelvis ‘tips’ backwards on the hips placing the joints and muscles of the pelvis and lower back at risk of strain and injury.
C. Collapsed Shoe-shaped foot: The lack of structural stability in the foot and restricted range of movement in the ankles causes the body weight fall forwards and the knees to roll inwards. Once the range in the knee joint is exhausted, the rest of the movement occurs via hip flexion, creating either a ‘hyper-lordotic’ posture of the lumbar spine, or forward flexion of the whole torso. A compliant shoe-shaped foot is associated with both knee and lower back pain during squatting.
RESTORING FOOT FUNCTION
Restoring foot function begins with restoring foot ‘form’ or shape. Just as the foot becomes shoe-shaped from wearing shoe-shaped shoes, the foot will become more foot-shaped by wearing foot-shaped shoes! The adaptation of the human body to the mechanical loads and stresses placed upon it is known as ‘Wolff’s law’ in biology. The key ingredients to restoring foot function are daily exposure to GRAVITY and MOVEMENT (the forces that create anatomical adaptation), and FUNCTIONAL FOOTWEAR (providing the ‘space’ for anatomical adaptation).
FUNCTIONAL FOOTWEAR DEFINED
1- Foot-shaped design (=toefreedom): A shoe should mimic the ‘fan-shape’ of a healthy unshod foot i.e. the widest part of the shoe should be the distance from the base of the great toe to the tip of the smallest toe (the toe-box). ‘Wide’ shoes that are not foot shaped are just as harmful to foot function as narrow shoe-shaped shoes
2- Flat sole: The weight–bearing area of the sole should be flat to the floor to provide maximum surface area
3- No toe-spring: The toes can only perform their stabilising role if they are in contact with the ground
HOW TO USE FUNCTIONAL FOOTWEAR
Based on simple physics, the demands on the movement system increase as the forces acting on the body increase (bodyweight) and/or stability decreases e.g. two feet to one foot to just the forefoot. Start using your functional footwear with the movements on the left and slowly progress towards the movements on the right.
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