What Really Goes On in Tadasana

Tadasana is the most basic of all Yoga asanas, but its importance should not be underestimated. The foundation of all standing asanas, Tadasana uses muscles in the feet, legs, core, back and glutes. A fellow classmate said “If you are not sweating in Tadasana, you are not in Tadasana”. Here’s why.
Since Tadasana is about rooting to the Earth, let’s analyse the asana from bottom up. Imagine four points on the soles of the feet: one on each side of the ball of the foot, and one on each side of the heel. The weight should be evenly distributed amongst these four points. By lifting your toes up, you will naturally be balancing on the soles of the feet. Rock forward and backward to find the extreme points of balance – you want to avoid these extremes and be on the four points evenly to provide a firm foundation for the rest of the body.
The knee caps (Patella) should be pulled up to avoid hyperextension of the knee, which wears out the ligaments. The function of the knee cap is also to provide a smooth gliding surface for movement of the knee joint, for example, in flexion and extention. Because the top part of the Patella inserts into the tendon of the Quadraceps Femoris muscle, engaging the knee cap activates the Quadraceps Femoris muscle which then moves the knee, hence, protecting the knee joint. Without the engagement of muscles, the force of the movement is directed to the meniscus (a cartilage) and the surrounding ligaments, which wears and tears more easily than they can repair themselves. This is one common knee problem faced by many.
Moving on to the middle portion of the body – the pelvic area. We all have a natural lower body arch. When doing any asanas, you would want to decrease this curve to lessen any pressure on the lower back. How this is done is by contracting the abdominal muscles which a) lifts the pelvis and in turn activates the erector spinae muscles in the lower back, and b) compresses all the abdominal muscles and produces an airbag effect to protect the lower back.
Another group of muscles which stabilises the pelvis are the glutes, comprising the Maximus, Medius and Minimus. Squeezing or contracting the glutes stabilises the pelvis by lengthening the lower back and bringing the pelvis to a neutral position. The glutes also work in tandem with the thigh muscles to stabilise the knee while standing. Engaging the glutes also leads to the engagement of both the internal and external thigh muscles, providing further muscular support and balance for the pose.
The hip flexors are another group of muscles responsible for maintaining pelvic balance. Once the lower back is lengthened, the hip flexors are activated to counter the natural tendency to anteriorly tilt the hips.
In short, in the correct muscle engagement, Tadasana co-activates the hip flexors and extensors, and the internal and external rotators to stabilise the pelvis and legs.
Finally, keep the shoulders broad in Tadasana. Think of drawing the shoulder blades back and downwards (adduct and depress the scapula) and opening the chest. The Rhomboids and Trapezius muscles work in tandem to bring about this action.
Glee (200-hour Yoga Teacher’s Training, weekday group)
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