Physiological Principles of Yoga Asanas (Postures).

CIRCULATION
Rhythmic movement stimulates the heart and lungs and circulation of blood and body fluids.

Feel the effects of lying with your legs up the wall for 5-10 minutes

The different positions of the body in the asanas exert a ‘squeeze and soak’ action, by which the organs and tissues are alternately compressed, squeezing blood out and then released, so fresh blood flows in.

The action of gravity drains the blood and fluids from particular areas of the body and increases the flow to others. Inverted poses, for example help drain and relax the legs and enhance circulation in the upper body. They also stimulate the stretch receptors in the carotid arteries thus lowering blood pressure. We often hear people being told to ‘put their feet up’, to relax and refresh the body and mind.

MUSCLE RELEASE / ‘STRETCHING’
This is a lengthening release of the muscles, rather than stretching. It liberates energy held in the muscles as excess tone or tension, relaxes them, increases their range of movement and overall flexibility and helps reduce the occurrence of injuries.

ALIGNMENT
Moving slowly and consciously into and out of postures, while taking care to keep the joints correctly positioned and working within a comfortable range helps correct muscular and skeletal imbalances. This improves posture, improves joint stability and reduces age related ‘wear and tear’.

BREATHING
Combining movement into and through sequences of postures with the breath and holding them with slow, deep breathing improves efficiency of breathing, blood circulation, energy (prana) levels and helps calm and focus the mind.

We can immediately feel the beneficial effects of even as simple a practice as breathing with arm movements 5-10x.

AWARENESS
Mindful attention to the breath and to specific body areas engages the mind and increases the blood flow and prana supply to the target area. This also develops interoception (internal awareness), improves mastery and control of the body and mental focus and lays the groundwork for meditation, leading to higher states of consciousness.

RELAXATION
In the conscious deep relaxation of ‘savasana’ (corpse pose) one systematically relaxes each part of the body releasing all the muscles and allowing the joints to open up. This thoroughly replenishes the body and calms the mind and the nervous system.

In this process, we can learn to observe the physical sensations, thoughts and emotions as ever-changing currents of energy, which flow through us, but are not the essence of who / what we are. Thus, yoga teaches us that consciousness and thoughts are not the same thing and helps to set us on the path to realising the true nature of being.

The postures can be done in different ways in different styles of yoga and for different
effects; Static / Dynamic or Restorative (see also Styles of Yoga).
Static holding of the poses builds strength and stability as well as flexibility and allows time to focus on details of alignment and mindfulness in the poses (e.g. Iyengar and non-trademarked hatha yoga styles).

Dynamic fast moving sequences, each linked by a ‘vinyasa’, build aerobic fitness, stimulate sweating, which softens the muscles and is thought to help eliminate toxins. They induce the release of endorphins, making it easier to perform more difficult poses (e.g. Astanga Vinyasa Yoga), but the slightly anaesthetising effect means there can be a higher risk of injury.

Slow moving dynamic sequences are more universally accessible and can be modified to
be varied and creative and to suit different ages and abilities (vinyasa flow). The dynamic styles are not suitable for people with depleted energy (chronic fatigue), recovering from illness or injury, at risk of fractures, suffering from anxiety or insomnia.

Restorative poses are generally passive, involve the use of supporting props and are held for long periods. They enable relaxation of the deep as well as surface muscles, which releases chronic tension in the body and can induce release of long held emotions (e.g. supported savasana above). Restorative yoga is useful for preparing for pranayama and meditation and is especially useful in yoga therapy.

You can view/ download some guidelines for establishing a yoga asana practice

Pranayama / Breathing Practices

Prana = vital energy, Yama = control.
Breath is our primary source of energy. Although basic breathing is an involuntary reflex, we can modify the way we breathe, both consciously and unconsciously. Many people tense up when anxious or stressed and their breath becomes shallow and rapid. This is very inefficient in terms of the amount of energy it takes to breathe compared with the amount derived from it. Under sustained stress such breathing patterns often become chronic. Vitality and mood drop and a vicious cycle develops.

The beginning pranayama practices teach how to use the whole breathing mechanism more efficiently and to experience how the breath helps relax the body, calm the mind,
improve energy and well-being.

Other practices cleanse the respiratory tract, heat / cool the body, energise particular body areas and internal organ systems, balance the nervous system, focus and calm the mind in preparation for meditation.

After much training (and purification through study, lifestyle and diet), the advanced pranayama practices help attain altered states of consciousness and prolong absorption in meditation.