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. Compliant Shoe-shaped Foot: The lack of structural stability in the foot and restricted range of movement in the ankles causes the body weight to 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.

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References

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Schoenfeld BJ. Squatting Kinematics and Kinetics and their Application to Exercise Performance. Journal of Strength and Conditioning Research (2010)

Myer GD et al. The Back Squat: A proposed assessment of functional deficits and technical factors that limit performance. Strength Cond J (2014)

Chandler T.J. & Stone MH. The Squat Exercise in Athletic Conditioning: A Review of the Literature. National Strength and Conditioning Association Journal (1991)

Chandler, J., McMilan, J., Kibler, B., & Richards, D. ACSM current comment safety of the squat exercise. Retrieved from www.acsm.org

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Schamberger W. The Malalignment Syndrome: Implications for Medicine and Sport. Churchill Livingstone (2002)

Wilkinson et al. Feet and Footwear: Applying Biological Design and Mismatch Theory to Running Injuries.
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