FOOT FUNCTION AND YOGA

 

Many people use yoga and its postures (Asanas) as a form of physical exercise to improve balance, increase flexibility and relieve stress. A fully functioning foot is essential to perform the different weight-bearing postures with correct alignment, especially in the standing balance postures such as the ‘tree’ and ‘eagle’.

 

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.

Literature
• Yu. SSY et al. The physical demands of the tree (Vriksasana) and one-leg balance (Utthita hasta Padangusthasana) poses performed by seniors: a biomechanical examination. Evidenced–Based Complementary and Alternative Medicine (2012) • Wang MY. The biomechanical demands of standing yoga poses in seniors: The yoga empowers seniors study (YESS). BMC Complementary and Alternative Medicine (2013) • Hayes M & Chase S. Prescribing Yoga. Primary Care: Clinics in Office Practice (2010) • Horak FB & Mancini M. Objective biomarkers of balance and gait for Parkinson’s Disease using body-worn sensors. Movement Disorders (2013) • Zhang X et al. Foot muscle morphology is related to center of pressure sway and control mechanisms during single-leg standing. Gait and Posture (2017) • Wilkinson et al. Feet and Footwear: Applying Biological Design and Mismatch Theory to Running Injuries. International Journal of Sports and Exercise Medicine 4:090 (2018)